browser(webkit): drag and drop on windows (#4889)

2024-12-14 13:45:36 +03:00 · 2021-01-06 09:46:35 -08:00 · 2021-01-06 09:46:35 -08:00 · cc1a79eceb
commit cc1a79eceb
parent f672033e11
2 changed files with 355 additions and 81 deletions
--- a/browser_patches/webkit/BUILD_NUMBER
+++ b/browser_patches/webkit/BUILD_NUMBER
@ -1,2 +1,2 @@
-1415
-Changed: yurys@chromium.org Tue 05 Jan 2021 03:48:12 PM PST
+1416
+Changed: joel.einbinder@gmail.com Wed, Jan  6, 2021  9:41:40 AM
--- a/browser_patches/webkit/patches/bootstrap.diff
+++ b/browser_patches/webkit/patches/bootstrap.diff
@ -5930,7 +5930,7 @@ index 1939fb90c22564d02cadf65bdaf7f65ccb7ce9a7..f6a73e6ac480ed0d9b964617d6aa62f3
 IntSize dragImageSize(DragImageRef)
 {
 diff --git a/Source/WebCore/platform/Pasteboard.h b/Source/WebCore/platform/Pasteboard.h
-index aadc46698df79564362a03f5dfe89b0eb7811ce9..6cba1018128280b36842d59b385d3de16893c4fb 100644
+index aadc46698df79564362a03f5dfe89b0eb7811ce9..382298e06bdeee546cfb3105ea21a63c4efe0a61 100644
 --- a/Source/WebCore/platform/Pasteboard.h
 +++ b/Source/WebCore/platform/Pasteboard.h
@@ -43,7 +43,7 @@ OBJC_CLASS NSString;
@ -5994,7 +5994,15 @@ index aadc46698df79564362a03f5dfe89b0eb7811ce9..6cba1018128280b36842d59b385d3de1
 #if PLATFORM(IOS_FAMILY)
     explicit Pasteboard(int64_t changeCount);
     explicit Pasteboard(const String& pasteboardName);
-@@ -333,6 +340,10 @@ private:
+@@ -286,6 +293,7 @@ public:
+     COMPtr<IDataObject> dataObject() const { return m_dataObject; }
+     void setExternalDataObject(IDataObject*);
+     const DragDataMap& dragDataMap() const { return m_dragDataMap; }
+    WEBCORE_EXPORT DragDataMap createDragDataMap();
+     void writeURLToWritableDataObject(const URL&, const String&);
+     COMPtr<WCDataObject> writableDataObject() const { return m_writableDataObject; }
+     void writeImageToDataObject(Element&, const URL&); // FIXME: Layering violation.
+@@ -333,6 +341,10 @@ private:
     String m_name;
 #endif
 
@ -6005,6 +6013,14 @@ index aadc46698df79564362a03f5dfe89b0eb7811ce9..6cba1018128280b36842d59b385d3de1
 #if PLATFORM(COCOA)
     String m_pasteboardName;
     int64_t m_changeCount;
+@@ -348,6 +360,7 @@ private:
+     COMPtr<IDataObject> m_dataObject;
+     COMPtr<WCDataObject> m_writableDataObject;
+     DragDataMap m_dragDataMap;
+    bool m_forDrag = false;
+ #endif
+ };
+ 
 diff --git a/Source/WebCore/platform/PlatformKeyboardEvent.h b/Source/WebCore/platform/PlatformKeyboardEvent.h
 index 1a1367f7a9df0ab1ace16d0365e55f6538d0cbd6..e24d748074295cc68f2eb89fb21adccc1acad149 100644
 --- a/Source/WebCore/platform/PlatformKeyboardEvent.h
@ -7220,6 +7236,54 @@ index 3ecf866005da6da9cec7c7930e6a4f93cb39d6e0..d81dc9ac0c433e00ab4ad73e20685609
     {
         RELEASE_ASSERT_NOT_REACHED();
     }
+diff --git a/Source/WebCore/platform/win/ClipboardUtilitiesWin.cpp b/Source/WebCore/platform/win/ClipboardUtilitiesWin.cpp
+index 8789f11c3643999c30dfdb1c9b939ae45bb0a51f..422961d2b43e6da9e36df4cdeb06fe91ac57a644 100644
+--- a/Source/WebCore/platform/win/ClipboardUtilitiesWin.cpp
+++ b/Source/WebCore/platform/win/ClipboardUtilitiesWin.cpp
+@@ -38,6 +38,7 @@
+ #include <wtf/text/CString.h>
+ #include <wtf/text/StringBuilder.h>
+ #include <wtf/text/win/WCharStringExtras.h>
+#include "Pasteboard.h"
+ 
+ #if USE(CF)
+ #include <CoreFoundation/CoreFoundation.h>
+@@ -724,7 +725,10 @@ template<typename T> void getStringData(IDataObject* data, FORMATETC* format, Ve
+     STGMEDIUM store;
+     if (FAILED(data->GetData(format, &store)))
+         return;
+-    dataStrings.append(String(static_cast<T*>(GlobalLock(store.hGlobal)), ::GlobalSize(store.hGlobal) / sizeof(T)));
+    // The string here should be null terminated, but it could come from another app so lets lock it
+    // to the size to prevent an overflow.
+    String rawString = String(static_cast<T*>(GlobalLock(store.hGlobal)), ::GlobalSize(store.hGlobal) / sizeof(T));
+    dataStrings.append(String::fromUTF8(rawString.utf8().data()));
+     GlobalUnlock(store.hGlobal);
+     ReleaseStgMedium(&store);
+ }
+diff --git a/Source/WebCore/platform/win/ClipboardUtilitiesWin.h b/Source/WebCore/platform/win/ClipboardUtilitiesWin.h
+index c50799b63e05adbe32bae3535d786c7d268f980f..9cf1cc7ec4eaae22947f80ba272dfae272167bd6 100644
+--- a/Source/WebCore/platform/win/ClipboardUtilitiesWin.h
+++ b/Source/WebCore/platform/win/ClipboardUtilitiesWin.h
+@@ -34,6 +34,7 @@ namespace WebCore {
+ 
+ class Document;
+ class DocumentFragment;
+class Pasteboard;
+ 
+ HGLOBAL createGlobalData(const String&);
+ HGLOBAL createGlobalData(const Vector<char>&);
+diff --git a/Source/WebCore/platform/win/DragDataWin.cpp b/Source/WebCore/platform/win/DragDataWin.cpp
+index 61ea4c47fa3522588f83a686d85c77c142909c24..4d377a6ca9e4c2f08e1f722391c853bd8cbf5109 100644
+--- a/Source/WebCore/platform/win/DragDataWin.cpp
+++ b/Source/WebCore/platform/win/DragDataWin.cpp
+@@ -48,6 +48,7 @@ DragData::DragData(const DragDataMap& data, const IntPoint& clientPosition, cons
+     , m_draggingSourceOperationMask(sourceOperationMask)
+     , m_applicationFlags(flags)
+     , m_dragDataMap(data)
+    , m_dragDestinationActionMask(anyDragDestinationAction())
+ {
+ }
+ 
 diff --git a/Source/WebCore/platform/win/KeyEventWin.cpp b/Source/WebCore/platform/win/KeyEventWin.cpp
 index 44737686187a06a92c408ea60b63a48ac8481334..c754a763688b52e7ddd47493296ef9b0c6adc527 100644
 --- a/Source/WebCore/platform/win/KeyEventWin.cpp
@ -7244,6 +7308,58 @@ index 44737686187a06a92c408ea60b63a48ac8481334..c754a763688b52e7ddd47493296ef9b0
 }
 
 bool PlatformKeyboardEvent::currentCapsLockState()
+diff --git a/Source/WebCore/platform/win/PasteboardWin.cpp b/Source/WebCore/platform/win/PasteboardWin.cpp
+index 21b97f58b0ee39e44721e6f27d07e62912eb04d7..c535c19a9e4bdf37966019d48b270982aad6d3a3 100644
+--- a/Source/WebCore/platform/win/PasteboardWin.cpp
+++ b/Source/WebCore/platform/win/PasteboardWin.cpp
+@@ -1131,7 +1131,21 @@ void Pasteboard::writeCustomData(const Vector<PasteboardCustomData>& data)
+     }
+ 
+     clear();
+    if (m_dataObject) {
+        const auto& customData = data.first();
+        customData.forEachPlatformString([&](auto& type, auto& string) {
+            writeString(type, string);
+        });
+ 
+        if (customData.hasSameOriginCustomData() || !customData.origin().isEmpty()) {
+            customData.forEachCustomString([&](auto& type, auto& string) {
+                writeString(type, string);
+            });
+        }
+        return;
+    }
+
+    // this is the real real clipboard. Prbaobly need to be doing drag data stuff.
+     if (::OpenClipboard(m_owner)) {
+         const auto& customData = data.first();
+         customData.forEachPlatformStringOrBuffer([](auto& type, auto& stringOrBuffer) {
+@@ -1170,4 +1184,25 @@ void Pasteboard::write(const Color&)
+ {
+ }
+ 
+DragDataMap Pasteboard::createDragDataMap() {
+    DragDataMap dragDataMap;
+    auto dragObject = dataObject();
+    if (!dragObject)
+        return dragDataMap;
+    // Enumerate clipboard content and load it in the map.
+    COMPtr<IEnumFORMATETC> itr;
+
+    if (FAILED(dragObject->EnumFormatEtc(DATADIR_GET, &itr)) || !itr)
+        return dragDataMap;
+
+    FORMATETC dataFormat;
+    while (itr->Next(1, &dataFormat, 0) == S_OK) {
+        Vector<String> dataStrings;
+        getClipboardData(dragObject.get(), &dataFormat, dataStrings);
+        if (!dataStrings.isEmpty())
+            dragDataMap.set(dataFormat.cfFormat, dataStrings);
+    }
+    return dragDataMap;
+}
+
+ } // namespace WebCore
 diff --git a/Source/WebCore/platform/wpe/DragDataWPE.cpp b/Source/WebCore/platform/wpe/DragDataWPE.cpp
 new file mode 100644
 index 0000000000000000000000000000000000000000..07fb260a5203167fdf94a552949394bb73ca8c61
@ -8122,7 +8238,7 @@ index 047c375a1bb77609912b123e66e4e330c3b60ecf..f3bab44d6876ba02f6b7eec02d4b22a7
     Cairo::Cairo
     Freetype::Freetype
 diff --git a/Source/WebKit/PlatformWin.cmake b/Source/WebKit/PlatformWin.cmake
-index 03af565ed1ae39e77e183a4aebd1e64a2e247e0a..26a0463f3e5a9973932c29bd2ea4cafc170b117a 100644
+index 03af565ed1ae39e77e183a4aebd1e64a2e247e0a..7bf35d77e8989d50bfb81b67909b6c828cf50dde 100644
 --- a/Source/WebKit/PlatformWin.cmake
 +++ b/Source/WebKit/PlatformWin.cmake
@@ -65,8 +65,12 @@ list(APPEND WebKit_SOURCES
@ -8138,7 +8254,15 @@ index 03af565ed1ae39e77e183a4aebd1e64a2e247e0a..26a0463f3e5a9973932c29bd2ea4cafc
     UIProcess/win/WebPageProxyWin.cpp
     UIProcess/win/WebPopupMenuProxyWin.cpp
     UIProcess/win/WebProcessPoolWin.cpp
-@@ -125,6 +129,63 @@ list(APPEND WebKit_INCLUDE_DIRECTORIES
+@@ -84,6 +88,7 @@ list(APPEND WebKit_SOURCES
+     WebProcess/Plugins/Netscape/win/PluginProxyWin.cpp
+ 
+     WebProcess/WebCoreSupport/win/WebPopupMenuWin.cpp
+    WebProcess/WebCoreSupport/win/WebDragClientWin.cpp
+ 
+     WebProcess/WebPage/AcceleratedSurface.cpp
+ 
+@@ -125,6 +130,63 @@ list(APPEND WebKit_INCLUDE_DIRECTORIES
     "${WEBKIT_DIR}/win"
 )
 
@ -8202,7 +8326,7 @@ index 03af565ed1ae39e77e183a4aebd1e64a2e247e0a..26a0463f3e5a9973932c29bd2ea4cafc
 set(WebKitCommonIncludeDirectories ${WebKit_INCLUDE_DIRECTORIES})
 set(WebKitCommonSystemIncludeDirectories ${WebKit_SYSTEM_INCLUDE_DIRECTORIES})
 
-@@ -177,6 +238,7 @@ if (${WTF_PLATFORM_WIN_CAIRO})
+@@ -177,6 +239,7 @@ if (${WTF_PLATFORM_WIN_CAIRO})
         OpenSSL::SSL
         mfuuid.lib
         strmiids.lib
@ -8287,7 +8411,7 @@ index b838fca9702c1432602176bb13ef052db224e82e..d802e555369176e74b37495ae924b04e
     NSEvent* nativeEvent() const { return m_nativeEvent.get(); }
 #elif PLATFORM(GTK)
 diff --git a/Source/WebKit/Shared/WebCoreArgumentCoders.cpp b/Source/WebKit/Shared/WebCoreArgumentCoders.cpp
-index faaa2adcf991b136593c55960646ff1f480cf1d7..771c9a318b16b407b5f737805c695cdefc9d510f 100644
+index faaa2adcf991b136593c55960646ff1f480cf1d7..d34282d7d42f0f4f3ea705ced8a5f6b5afeef80f 100644
 --- a/Source/WebKit/Shared/WebCoreArgumentCoders.cpp
 +++ b/Source/WebKit/Shared/WebCoreArgumentCoders.cpp
@@ -113,6 +113,10 @@
@ -8333,6 +8457,51 @@ index faaa2adcf991b136593c55960646ff1f480cf1d7..771c9a318b16b407b5f737805c695cde
     return true;
 }
 
+@@ -1431,6 +1444,11 @@ void ArgumentCoder<DragData>::encode(Encoder& encoder, const DragData& dragData)
+ #if PLATFORM(COCOA)
+     encoder << dragData.pasteboardName();
+     encoder << dragData.fileNames();
+#endif
+#if PLATFORM(WIN)
+    DragData dragDataCopy = dragData;
+    HashMap<unsigned int, Vector<String>> hash = dragDataCopy.dragDataMap();
+    encoder << hash;
+ #endif
+     encoder << dragData.dragDestinationActionMask();
+ }
+@@ -1453,9 +1471,16 @@ bool ArgumentCoder<DragData>::decode(Decoder& decoder, DragData& dragData)
+     if (!decoder.decode(applicationFlags))
+         return false;
+ 
+#if PLATFORM(WIN)
+    DragDataMap dragDataMap;
+    if (!decoder.decode(dragDataMap))
+        return false;
+#else
+     String pasteboardName;
+-    Vector<String> fileNames;
+#endif
+
+ #if PLATFORM(COCOA)
+    Vector<String> fileNames;
+     if (!decoder.decode(pasteboardName))
+         return false;
+ 
+@@ -1467,8 +1492,14 @@ bool ArgumentCoder<DragData>::decode(Decoder& decoder, DragData& dragData)
+     if (!decoder.decode(dragDestinationActionMask))
+         return false;
+ 
+#if PLATFORM(WIN)
+    dragData = DragData(dragDataMap, clientPosition, globalPosition, draggingSourceOperationMask, applicationFlags);
+#else
+     dragData = DragData(pasteboardName, clientPosition, globalPosition, draggingSourceOperationMask, applicationFlags, dragDestinationActionMask);
+#endif
+#if PLATFORM(COCOA)
+     dragData.setFileNames(fileNames);
+#endif
+ 
+     return true;
+ }
 diff --git a/Source/WebKit/Shared/WebEvent.h b/Source/WebKit/Shared/WebEvent.h
 index 3ae6504779d3917a79f69f32b58260afeda270b4..72d44c33953cc13bf2ed7c762b4f9a7b88571b56 100644
 --- a/Source/WebKit/Shared/WebEvent.h
@ -14133,10 +14302,10 @@ index 0000000000000000000000000000000000000000..1353851472668b3e77c19db54f224c0c
 +} // namespace WebKit
 diff --git a/Source/WebKit/UIProcess/WebPageInspectorInputAgent.cpp b/Source/WebKit/UIProcess/WebPageInspectorInputAgent.cpp
 new file mode 100644
-index 0000000000000000000000000000000000000000..66526175997380bc8ac99d7f3d1941b72cf95be6
+index 0000000000000000000000000000000000000000..f92482b8ba7fd65727024f2f802a5927d8dc5a4d
 --- /dev/null
 +++ b/Source/WebKit/UIProcess/WebPageInspectorInputAgent.cpp
-@@ -0,0 +1,294 @@
+@@ -0,0 +1,290 @@
 +/*
 + * Copyright (C) 2019 Microsoft Corporation.
 + *
@ -14314,7 +14483,7 @@ index 0000000000000000000000000000000000000000..66526175997380bc8ac99d7f3d1941b7
 +        eventIsSystemKey = *isSystemKey;
 +    WallTime timestamp = WallTime::now();
 +
-+#if PLATFORM(GTK) || PLATFORM(WPE)
+#if !PLATFORM(COCOA)
 +    // cancel any active drag on Escape
 +    if (eventType == WebKit::WebEvent::KeyDown && key == "Escape" && m_page.cancelDragIfNeeded()) {
 +        callback->sendSuccess();
@ -14412,17 +14581,13 @@ index 0000000000000000000000000000000000000000..66526175997380bc8ac99d7f3d1941b7
 +        eventClickCount,
 +        eventModifiers,
 +        timestamp);
-+#if PLATFORM(WPE) || PLATFORM(GTK)
 +    // We intercept any drags generated by this mouse event
 +    // to prevent them from creating actual drags in the host
 +    // operating system.
 +    m_page.setInterceptDrags(true);
-+#endif
 +    m_page.handleMouseEvent(event);
-+#if PLATFORM(WPE) || PLATFORM(GTK)
 +    m_page.setInterceptDrags(false);
 +#endif
-+#endif
 +}
 +
 +void WebPageInspectorInputAgent::dispatchTapEvent(int x, int y, Optional<int>&& modifiers, Ref<DispatchTapEventCallback>&& callback) {
@ -14523,7 +14688,7 @@ index 0000000000000000000000000000000000000000..01b8f65e87b4898b1418f47f4d95c401
 +
 +} // namespace WebKit
 diff --git a/Source/WebKit/UIProcess/WebPageProxy.cpp b/Source/WebKit/UIProcess/WebPageProxy.cpp
-index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a350ccb0aa8 100644
+index 5716d67d700e2d1a97b304a2949aabca24358d5c..9b63c511180c50907a3719ae854571adb58b5a2f 100644
 --- a/Source/WebKit/UIProcess/WebPageProxy.cpp
 +++ b/Source/WebKit/UIProcess/WebPageProxy.cpp
@@ -236,7 +236,7 @@
@ -14627,7 +14792,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 {
     if (!hasRunningProcess())
         return;
-+#if PLATFORM(GTK) || PLATFORM(WPE)
+#if !PLATFORM(COCOA)
 +    if (action == DragControllerAction::Entered || action == DragControllerAction::Updated)
 +        m_dragEventsQueued++;
 +#endif
@ -14643,11 +14808,11 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     send(Messages::WebPage::PerformDragControllerAction(action, dragData.clientPosition(), dragData.globalPosition(), dragData.draggingSourceOperationMask(), *dragData.platformData(), dragData.flags()));
 #else
     send(Messages::WebPage::PerformDragControllerAction(action, dragData, sandboxExtensionHandle, sandboxExtensionsForUpload));
-@@ -2465,13 +2531,26 @@ void WebPageProxy::didPerformDragControllerAction(Optional<WebCore::DragOperatio
+@@ -2465,18 +2531,43 @@ void WebPageProxy::didPerformDragControllerAction(Optional<WebCore::DragOperatio
     m_currentDragCaretEditableElementRect = editableElementRect;
     setDragCaretRect(insertionRect);
     pageClient().didPerformDragControllerAction();
-+#if PLATFORM(GTK) || PLATFORM(WPE)
+#if !PLATFORM(COCOA)
 +    m_dragEventsQueued--;
 +    if (m_dragEventsQueued == 0 && m_mouseEventQueue.isEmpty())
 +        m_inspectorController->didProcessAllPendingMouseEvents();
@ -14673,11 +14838,27 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 
     didStartDrag();
 }
-@@ -2485,6 +2564,16 @@ void WebPageProxy::dragEnded(const IntPoint& clientPosition, const IntPoint& glo
+ #endif
+ 
+#if PLATFORM(WIN) && ENABLE(DRAG_SUPPORT)
+void WebPageProxy::startDrag(WebCore::DragDataMap& dragDataMap)
+{
+    if (m_interceptDrags) {
+        m_dragSelectionData = dragDataMap;
+        m_dragSourceOperationMask = WebCore::anyDragOperation();
+    }
+    didStartDrag();
+}
+#endif
+
+
+ void WebPageProxy::dragEnded(const IntPoint& clientPosition, const IntPoint& globalPosition, OptionSet<WebCore::DragOperation> dragOperationMask)
+ {
+     if (!hasRunningProcess())
+@@ -2485,6 +2576,14 @@ void WebPageProxy::dragEnded(const IntPoint& clientPosition, const IntPoint& glo
     setDragCaretRect({ });
 }
 
-+#if PLATFORM(GTK) || PLATFORM(WPE)
 +bool WebPageProxy::cancelDragIfNeeded() {
 +    if (!m_dragSelectionData)
 +        return false;
@ -14685,35 +14866,37 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 +    dragEnded(m_lastMousePositionForDrag, IntPoint(), m_dragSourceOperationMask);
 +    return true;
 +}
-+#endif
 +
 void WebPageProxy::didPerformDragOperation(bool handled)
 {
     pageClient().didPerformDragOperation(handled);
-@@ -2497,6 +2586,14 @@ void WebPageProxy::didStartDrag()
+@@ -2497,8 +2596,18 @@ void WebPageProxy::didStartDrag()
 
     discardQueuedMouseEvents();
     send(Messages::WebPage::DidStartDrag());
 +
-+#if PLATFORM(GTK) || PLATFORM(WPE)
 +    if (m_interceptDrags) {
+#if PLATFORM(COCOA) || PLATFORM(WIN)
+        DragData dragData(*m_dragSelectionData, m_lastMousePositionForDrag, WebCore::IntPoint(), m_dragSourceOperationMask);
+#else
 +        DragData dragData(&*m_dragSelectionData, m_lastMousePositionForDrag, WebCore::IntPoint(), m_dragSourceOperationMask);
+#endif
 +        dragEntered(dragData);
 +        dragUpdated(dragData);
 +    }
-+#endif
 }
-     
+-    
+
 void WebPageProxy::dragCancelled()
-@@ -2603,16 +2700,38 @@ void WebPageProxy::processNextQueuedMouseEvent()
+ {
+     if (hasRunningProcess())
+@@ -2603,16 +2712,38 @@ void WebPageProxy::processNextQueuedMouseEvent()
         m_process->startResponsivenessTimer();
     }
 
 -    Optional<SandboxExtension::HandleArray> sandboxExtensions;
-+#if PLATFORM(GTK) || PLATFORM(WPE)
 +    m_lastMousePositionForDrag = event.position();
 +    if (!m_dragSelectionData) {
-+#endif
 +        Optional<SandboxExtension::HandleArray> sandboxExtensions;
 
 #if PLATFORM(MAC)
@ -14723,13 +14906,19 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 +        bool eventMayStartDrag = !m_currentDragOperation && eventType == WebEvent::MouseMove && event.button() != WebMouseEvent::Button::NoButton;
 +        if (eventMayStartDrag)
 +            sandboxExtensions = SandboxExtension::createHandlesForMachLookup({ "com.apple.iconservices"_s, "com.apple.iconservices.store"_s }, WTF::nullopt);
-+#endif
+ #endif
+-    
+-    LOG(MouseHandling, "UIProcess: sent mouse event %s (queue size %zu)", webMouseEventTypeString(eventType), m_mouseEventQueue.size());
+-    send(Messages::WebPage::MouseEvent(event, sandboxExtensions));
 +
 +        LOG(MouseHandling, "UIProcess: sent mouse event %s (queue size %zu)", webMouseEventTypeString(eventType), m_mouseEventQueue.size());
 +        send(Messages::WebPage::MouseEvent(event, sandboxExtensions));
-+#if PLATFORM(GTK) || PLATFORM(WPE)
 +    } else {
+#if PLATFORM(COCOA) || PLATFORM(WIN)
+        DragData dragData(*m_dragSelectionData, event.position(), event.globalPosition(), m_dragSourceOperationMask);
+#else
 +        DragData dragData(&*m_dragSelectionData, event.position(), event.globalPosition(), m_dragSourceOperationMask);
+#endif
 +        if (eventType == WebEvent::MouseMove) {
 +            dragUpdated(dragData);
 +        } else if (eventType == WebEvent::MouseUp) {
@ -14744,14 +14933,10 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 +        }
 +        didReceiveEvent(eventType, true);
 +    }
- #endif
-    
-    LOG(MouseHandling, "UIProcess: sent mouse event %s (queue size %zu)", webMouseEventTypeString(eventType), m_mouseEventQueue.size());
-    send(Messages::WebPage::MouseEvent(event, sandboxExtensions));
 }
 
 void WebPageProxy::doAfterProcessingAllPendingMouseEvents(WTF::Function<void ()>&& action)
-@@ -2793,7 +2912,7 @@ static TrackingType mergeTrackingTypes(TrackingType a, TrackingType b)
+@@ -2793,7 +2924,7 @@ static TrackingType mergeTrackingTypes(TrackingType a, TrackingType b)
 
 void WebPageProxy::updateTouchEventTracking(const WebTouchEvent& touchStartEvent)
 {
@ -14760,7 +14945,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     const EventNames& names = eventNames();
     for (auto& touchPoint : touchStartEvent.touchPoints()) {
         IntPoint location = touchPoint.location();
-@@ -2826,7 +2945,7 @@ void WebPageProxy::updateTouchEventTracking(const WebTouchEvent& touchStartEvent
+@@ -2826,7 +2957,7 @@ void WebPageProxy::updateTouchEventTracking(const WebTouchEvent& touchStartEvent
     m_touchAndPointerEventTracking.touchStartTracking = TrackingType::Synchronous;
     m_touchAndPointerEventTracking.touchMoveTracking = TrackingType::Synchronous;
     m_touchAndPointerEventTracking.touchEndTracking = TrackingType::Synchronous;
@ -14769,7 +14954,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 }
 
 TrackingType WebPageProxy::touchEventTrackingType(const WebTouchEvent& touchStartEvent) const
-@@ -3245,6 +3364,7 @@ void WebPageProxy::receivedNavigationPolicyDecision(PolicyAction policyAction, A
+@@ -3245,6 +3376,7 @@ void WebPageProxy::receivedNavigationPolicyDecision(PolicyAction policyAction, A
 
 void WebPageProxy::receivedPolicyDecision(PolicyAction action, API::Navigation* navigation, RefPtr<API::WebsitePolicies>&& websitePolicies, Variant<Ref<API::NavigationResponse>, Ref<API::NavigationAction>>&& navigationActionOrResponse, Ref<PolicyDecisionSender>&& sender, Optional<SandboxExtension::Handle> sandboxExtensionHandle, WillContinueLoadInNewProcess willContinueLoadInNewProcess)
 {
@ -14777,7 +14962,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     if (!hasRunningProcess()) {
         sender->send(PolicyDecision { sender->identifier(), isNavigatingToAppBoundDomain(), PolicyAction::Ignore, 0, WTF::nullopt, WTF::nullopt });
         return;
-@@ -3954,6 +4074,11 @@ void WebPageProxy::pageScaleFactorDidChange(double scaleFactor)
+@@ -3954,6 +4086,11 @@ void WebPageProxy::pageScaleFactorDidChange(double scaleFactor)
     m_pageScaleFactor = scaleFactor;
 }
 
@ -14789,7 +14974,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 void WebPageProxy::pluginScaleFactorDidChange(double pluginScaleFactor)
 {
     m_pluginScaleFactor = pluginScaleFactor;
-@@ -4370,6 +4495,7 @@ void WebPageProxy::didDestroyNavigation(uint64_t navigationID)
+@@ -4370,6 +4507,7 @@ void WebPageProxy::didDestroyNavigation(uint64_t navigationID)
 
     // FIXME: Message check the navigationID.
     m_navigationState->didDestroyNavigation(navigationID);
@ -14797,7 +14982,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 }
 
 void WebPageProxy::didStartProvisionalLoadForFrame(FrameIdentifier frameID, FrameInfoData&& frameInfo, ResourceRequest&& request, uint64_t navigationID, URL&& url, URL&& unreachableURL, const UserData& userData)
-@@ -4592,6 +4718,8 @@ void WebPageProxy::didFailProvisionalLoadForFrameShared(Ref<WebProcessProxy>&& p
+@@ -4592,6 +4730,8 @@ void WebPageProxy::didFailProvisionalLoadForFrameShared(Ref<WebProcessProxy>&& p
 
     m_failingProvisionalLoadURL = { };
 
@ -14806,7 +14991,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     // If the provisional page's load fails then we destroy the provisional page.
     if (m_provisionalPage && m_provisionalPage->mainFrame() == frame && willContinueLoading == WillContinueLoading::No)
         m_provisionalPage = nullptr;
-@@ -5040,7 +5168,14 @@ void WebPageProxy::decidePolicyForNavigationActionAsync(FrameIdentifier frameID,
+@@ -5040,7 +5180,14 @@ void WebPageProxy::decidePolicyForNavigationActionAsync(FrameIdentifier frameID,
     NavigationActionData&& navigationActionData, FrameInfoData&& originatingFrameInfo, Optional<WebPageProxyIdentifier> originatingPageID, const WebCore::ResourceRequest& originalRequest, WebCore::ResourceRequest&& request,
     IPC::FormDataReference&& requestBody, WebCore::ResourceResponse&& redirectResponse, const UserData& userData, uint64_t listenerID)
 {
@ -14822,7 +15007,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 }
 
 void WebPageProxy::decidePolicyForNavigationActionAsyncShared(Ref<WebProcessProxy>&& process, PageIdentifier webPageID, FrameIdentifier frameID, FrameInfoData&& frameInfo,
-@@ -5554,6 +5689,7 @@ void WebPageProxy::createNewPage(FrameInfoData&& originatingFrameInfoData, WebPa
+@@ -5554,6 +5701,7 @@ void WebPageProxy::createNewPage(FrameInfoData&& originatingFrameInfoData, WebPa
     auto* originatingPage = m_process->webPage(originatingPageID);
     auto originatingFrameInfo = API::FrameInfo::create(WTFMove(originatingFrameInfoData), originatingPage);
     auto mainFrameURL = m_mainFrame ? m_mainFrame->url() : URL();
@ -14830,7 +15015,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     auto completionHandler = [this, protectedThis = makeRef(*this), mainFrameURL, request, reply = WTFMove(reply), privateClickMeasurement = navigationActionData.privateClickMeasurement] (RefPtr<WebPageProxy> newPage) mutable {
         if (!newPage) {
             reply(WTF::nullopt, WTF::nullopt);
-@@ -5594,6 +5730,7 @@ void WebPageProxy::createNewPage(FrameInfoData&& originatingFrameInfoData, WebPa
+@@ -5594,6 +5742,7 @@ void WebPageProxy::createNewPage(FrameInfoData&& originatingFrameInfoData, WebPa
 void WebPageProxy::showPage()
 {
     m_uiClient->showPage(this);
@ -14838,7 +15023,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 }
 
 void WebPageProxy::exitFullscreenImmediately()
-@@ -5629,6 +5766,10 @@ void WebPageProxy::closePage()
+@@ -5629,6 +5778,10 @@ void WebPageProxy::closePage()
     if (isClosed())
         return;
 
@ -14849,7 +15034,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     RELEASE_LOG_IF_ALLOWED(Process, "closePage:");
     pageClient().clearAllEditCommands();
     m_uiClient->close(this);
-@@ -5648,6 +5789,8 @@ void WebPageProxy::runJavaScriptAlert(FrameIdentifier frameID, FrameInfoData&& f
+@@ -5648,6 +5801,8 @@ void WebPageProxy::runJavaScriptAlert(FrameIdentifier frameID, FrameInfoData&& f
         if (auto* automationSession = process().processPool().automationSession())
             automationSession->willShowJavaScriptDialog(*this);
     }
@ -14858,7 +15043,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     m_uiClient->runJavaScriptAlert(*this, message, frame, WTFMove(frameInfo), WTFMove(reply));
 }
 
-@@ -5665,6 +5808,8 @@ void WebPageProxy::runJavaScriptConfirm(FrameIdentifier frameID, FrameInfoData&&
+@@ -5665,6 +5820,8 @@ void WebPageProxy::runJavaScriptConfirm(FrameIdentifier frameID, FrameInfoData&&
         if (auto* automationSession = process().processPool().automationSession())
             automationSession->willShowJavaScriptDialog(*this);
     }
@ -14867,7 +15052,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 
     m_uiClient->runJavaScriptConfirm(*this, message, frame, WTFMove(frameInfo), WTFMove(reply));
 }
-@@ -5683,6 +5828,8 @@ void WebPageProxy::runJavaScriptPrompt(FrameIdentifier frameID, FrameInfoData&&
+@@ -5683,6 +5840,8 @@ void WebPageProxy::runJavaScriptPrompt(FrameIdentifier frameID, FrameInfoData&&
         if (auto* automationSession = process().processPool().automationSession())
             automationSession->willShowJavaScriptDialog(*this);
     }
@ -14876,7 +15061,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 
     m_uiClient->runJavaScriptPrompt(*this, message, defaultValue, frame, WTFMove(frameInfo), WTFMove(reply));
 }
-@@ -5838,6 +5985,8 @@ void WebPageProxy::runBeforeUnloadConfirmPanel(FrameIdentifier frameID, FrameInf
+@@ -5838,6 +5997,8 @@ void WebPageProxy::runBeforeUnloadConfirmPanel(FrameIdentifier frameID, FrameInf
             return;
         }
     }
@ -14885,18 +15070,18 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 
     // Since runBeforeUnloadConfirmPanel() can spin a nested run loop we need to turn off the responsiveness timer and the tryClose timer.
     m_process->stopResponsivenessTimer();
-@@ -7015,6 +7164,10 @@ void WebPageProxy::didReceiveEvent(uint32_t opaqueType, bool handled)
+@@ -7015,6 +7176,10 @@ void WebPageProxy::didReceiveEvent(uint32_t opaqueType, bool handled)
             if (auto* automationSession = process().processPool().automationSession())
                 automationSession->mouseEventsFlushedForPage(*this);
             didFinishProcessingAllPendingMouseEvents();
-+#if PLATFORM(GTK) || PLATFORM(WPE)
+#if !PLATFORM(COCOA)
 +            if (m_dragEventsQueued == 0)
 +#endif
 +                m_inspectorController->didProcessAllPendingMouseEvents();
         }
         break;
     }
-@@ -7041,7 +7194,6 @@ void WebPageProxy::didReceiveEvent(uint32_t opaqueType, bool handled)
+@@ -7041,7 +7206,6 @@ void WebPageProxy::didReceiveEvent(uint32_t opaqueType, bool handled)
     case WebEvent::RawKeyDown:
     case WebEvent::Char: {
         LOG(KeyHandling, "WebPageProxy::didReceiveEvent: %s (queue empty %d)", webKeyboardEventTypeString(type), m_keyEventQueue.isEmpty());
@ -14904,7 +15089,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
         MESSAGE_CHECK(m_process, !m_keyEventQueue.isEmpty());
         auto event = m_keyEventQueue.takeFirst();
         MESSAGE_CHECK(m_process, type == event.type());
-@@ -7060,7 +7212,6 @@ void WebPageProxy::didReceiveEvent(uint32_t opaqueType, bool handled)
+@@ -7060,7 +7224,6 @@ void WebPageProxy::didReceiveEvent(uint32_t opaqueType, bool handled)
         // The call to doneWithKeyEvent may close this WebPage.
         // Protect against this being destroyed.
         Ref<WebPageProxy> protect(*this);
@ -14912,7 +15097,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
         pageClient().doneWithKeyEvent(event, handled);
         if (!handled)
             m_uiClient->didNotHandleKeyEvent(this, event);
-@@ -7069,6 +7220,7 @@ void WebPageProxy::didReceiveEvent(uint32_t opaqueType, bool handled)
+@@ -7069,6 +7232,7 @@ void WebPageProxy::didReceiveEvent(uint32_t opaqueType, bool handled)
         if (!canProcessMoreKeyEvents) {
             if (auto* automationSession = process().processPool().automationSession())
                 automationSession->keyboardEventsFlushedForPage(*this);
@ -14920,7 +15105,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
         }
         break;
     }
-@@ -7484,7 +7636,6 @@ static bool shouldReloadAfterProcessTermination(ProcessTerminationReason reason)
+@@ -7484,7 +7648,6 @@ static bool shouldReloadAfterProcessTermination(ProcessTerminationReason reason)
 void WebPageProxy::dispatchProcessDidTerminate(ProcessTerminationReason reason)
 {
     RELEASE_LOG_ERROR_IF_ALLOWED(Loading, "dispatchProcessDidTerminate: reason = %d", reason);
@ -14928,7 +15113,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     // We notify the client asynchronously because several pages may share the same process
     // and we want to make sure all pages are aware their process has crashed before the
     // the client reacts to the process termination.
-@@ -7492,7 +7643,10 @@ void WebPageProxy::dispatchProcessDidTerminate(ProcessTerminationReason reason)
+@@ -7492,7 +7655,10 @@ void WebPageProxy::dispatchProcessDidTerminate(ProcessTerminationReason reason)
         if (!weakThis)
             return;
 
@ -14940,7 +15125,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
         if (m_loaderClient)
             handledByClient = reason != ProcessTerminationReason::RequestedByClient && m_loaderClient->processDidCrash(*this);
         else
-@@ -7852,6 +8006,7 @@ static const Vector<ASCIILiteral>& mediaRelatedIOKitClasses()
+@@ -7852,6 +8018,7 @@ static const Vector<ASCIILiteral>& mediaRelatedIOKitClasses()
 
 WebPageCreationParameters WebPageProxy::creationParameters(WebProcessProxy& process, DrawingAreaProxy& drawingArea, RefPtr<API::WebsitePolicies>&& websitePolicies)
 {
@ -14948,7 +15133,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     WebPageCreationParameters parameters;
 
     parameters.processDisplayName = configuration().processDisplayName();
-@@ -8024,6 +8179,8 @@ WebPageCreationParameters WebPageProxy::creationParameters(WebProcessProxy& proc
+@@ -8024,6 +8191,8 @@ WebPageCreationParameters WebPageProxy::creationParameters(WebProcessProxy& proc
     parameters.shouldRelaxThirdPartyCookieBlocking = m_configuration->shouldRelaxThirdPartyCookieBlocking();
     parameters.canUseCredentialStorage = m_canUseCredentialStorage;
 
@ -14957,7 +15142,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
 #if PLATFORM(GTK)
     parameters.themeName = pageClient().themeName();
 #endif
-@@ -8095,6 +8252,14 @@ void WebPageProxy::gamepadActivity(const Vector<GamepadData>& gamepadDatas, Even
+@@ -8095,6 +8264,14 @@ void WebPageProxy::gamepadActivity(const Vector<GamepadData>& gamepadDatas, Even
 
 void WebPageProxy::didReceiveAuthenticationChallengeProxy(Ref<AuthenticationChallengeProxy>&& authenticationChallenge, NegotiatedLegacyTLS negotiatedLegacyTLS)
 {
@ -14972,7 +15157,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     if (negotiatedLegacyTLS == NegotiatedLegacyTLS::Yes) {
         m_navigationClient->shouldAllowLegacyTLS(*this, authenticationChallenge.get(), [this, protectedThis = makeRef(*this), authenticationChallenge] (bool shouldAllowLegacyTLS) {
             if (shouldAllowLegacyTLS)
-@@ -8180,7 +8345,8 @@ void WebPageProxy::requestGeolocationPermissionForFrame(GeolocationIdentifier ge
+@@ -8180,7 +8357,8 @@ void WebPageProxy::requestGeolocationPermissionForFrame(GeolocationIdentifier ge
     MESSAGE_CHECK(m_process, frame);
 
     // FIXME: Geolocation should probably be using toString() as its string representation instead of databaseIdentifier().
@ -14982,7 +15167,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     auto request = m_geolocationPermissionRequestManager.createRequest(geolocationID);
     Function<void(bool)> completionHandler = [request = WTFMove(request)](bool allowed) {
         if (allowed)
-@@ -8189,6 +8355,14 @@ void WebPageProxy::requestGeolocationPermissionForFrame(GeolocationIdentifier ge
+@@ -8189,6 +8367,14 @@ void WebPageProxy::requestGeolocationPermissionForFrame(GeolocationIdentifier ge
             request->deny();
     };
 
@ -14998,7 +15183,7 @@ index 5716d67d700e2d1a97b304a2949aabca24358d5c..57ade9830b106e7d9c2dba6dc2322a35
     // and make it one UIClient call that calls the completionHandler with false
     // if there is no delegate instead of returning the completionHandler
 diff --git a/Source/WebKit/UIProcess/WebPageProxy.h b/Source/WebKit/UIProcess/WebPageProxy.h
-index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c16b18524c 100644
+index 0df616b76fb75033ef20179fe5b296f28355e3e1..e641744506cb9103f0a79351fb6fab51bcf46ea0 100644
 --- a/Source/WebKit/UIProcess/WebPageProxy.h
 +++ b/Source/WebKit/UIProcess/WebPageProxy.h
@@ -39,6 +39,7 @@
@ -15024,7 +15209,15 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
 #if ENABLE(WIRELESS_PLAYBACK_TARGET) && !PLATFORM(IOS_FAMILY)
 #include <WebCore/MediaPlaybackTargetPicker.h>
 #include <WebCore/WebMediaSessionManagerClient.h>
-@@ -224,7 +233,6 @@ class GraphicsLayer;
+@@ -217,6 +226,7 @@ class AuthenticationChallenge;
+ class CertificateInfo;
+ class Cursor;
+ class DragData;
+typedef HashMap<unsigned, Vector<String>> DragDataMap;
+ class FloatRect;
+ class FontAttributeChanges;
+ class FontChanges;
+@@ -224,7 +234,6 @@ class GraphicsLayer;
 class IntSize;
 class ProtectionSpace;
 class RunLoopObserver;
@ -15032,7 +15225,7 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
 class SharedBuffer;
 class TextIndicator;
 class ValidationBubble;
-@@ -515,6 +523,8 @@ public:
+@@ -515,6 +524,8 @@ public:
     void setControlledByAutomation(bool);
 
     WebPageInspectorController& inspectorController() { return *m_inspectorController; }
@ -15041,7 +15234,7 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
 
 #if PLATFORM(IOS_FAMILY)
     void showInspectorIndication();
-@@ -586,6 +596,11 @@ public:
+@@ -586,6 +597,11 @@ public:
 
     void setPageLoadStateObserver(std::unique_ptr<PageLoadState::Observer>&&);
 
@ -15053,7 +15246,7 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
     void initializeWebPage();
     void setDrawingArea(std::unique_ptr<DrawingAreaProxy>&&);
 
-@@ -611,6 +626,7 @@ public:
+@@ -611,6 +627,7 @@ public:
     void closePage();
 
     void addPlatformLoadParameters(WebProcessProxy&, LoadParameters&);
@ -15061,7 +15254,7 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
     RefPtr<API::Navigation> loadRequest(WebCore::ResourceRequest&&, WebCore::ShouldOpenExternalURLsPolicy = WebCore::ShouldOpenExternalURLsPolicy::ShouldAllowExternalSchemesButNotAppLinks, API::Object* userData = nullptr);
     RefPtr<API::Navigation> loadFile(const String& fileURL, const String& resourceDirectoryURL, API::Object* userData = nullptr);
     RefPtr<API::Navigation> loadData(const IPC::DataReference&, const String& MIMEType, const String& encoding, const String& baseURL, API::Object* userData = nullptr, WebCore::ShouldOpenExternalURLsPolicy = WebCore::ShouldOpenExternalURLsPolicy::ShouldNotAllow);
-@@ -1113,6 +1129,7 @@ public:
+@@ -1113,6 +1130,7 @@ public:
 #endif
 
     void pageScaleFactorDidChange(double);
@ -15069,19 +15262,25 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
     void pluginScaleFactorDidChange(double);
     void pluginZoomFactorDidChange(double);
 
-@@ -1192,8 +1209,10 @@ public:
+@@ -1191,10 +1209,16 @@ public:
+     void startDrag(const WebCore::DragItem&, const ShareableBitmap::Handle& dragImageHandle);
     void setPromisedDataForImage(const String& pasteboardName, const SharedMemory::IPCHandle& imageHandle, const String& filename, const String& extension,
         const String& title, const String& url, const String& visibleURL, const SharedMemory::IPCHandle& archiveHandle);
+#else
+    void setInterceptDrags(bool shouldIntercept) { m_interceptDrags = true; };
+    bool cancelDragIfNeeded();
 #endif
 -#if PLATFORM(GTK)
 +#if PLATFORM(GTK) || PLATFORM(WPE)
     void startDrag(WebCore::SelectionData&&, OptionSet<WebCore::DragOperation>, const ShareableBitmap::Handle& dragImage);
-+    void setInterceptDrags(bool shouldIntercept) { m_interceptDrags = true; };
-+    bool cancelDragIfNeeded();
 #endif
+#if PLATFORM(WIN)
+    void startDrag(WebCore::DragDataMap& dragDataMap);
+#endif
 #endif
 
-@@ -1433,6 +1452,8 @@ public:
+     void processDidBecomeUnresponsive();
+@@ -1433,6 +1457,8 @@ public:
 
 #if PLATFORM(COCOA) || PLATFORM(GTK)
     RefPtr<ViewSnapshot> takeViewSnapshot(Optional<WebCore::IntRect>&&);
@ -15090,7 +15289,7 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
 #endif
 
 #if ENABLE(WEB_CRYPTO)
-@@ -2450,6 +2471,7 @@ private:
+@@ -2450,6 +2476,7 @@ private:
     String m_overrideContentSecurityPolicy;
 
     RefPtr<WebInspectorProxy> m_inspector;
@ -15098,21 +15297,26 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
 
 #if ENABLE(FULLSCREEN_API)
     std::unique_ptr<WebFullScreenManagerProxy> m_fullScreenManager;
-@@ -2683,6 +2705,13 @@ private:
+@@ -2683,6 +2710,18 @@ private:
     unsigned m_currentDragNumberOfFilesToBeAccepted { 0 };
     WebCore::IntRect m_currentDragCaretRect;
     WebCore::IntRect m_currentDragCaretEditableElementRect;
-+#if PLATFORM(GTK) || PLATFORM(WPE)
+#if !PLATOFORM(COCOA)
 +    bool m_interceptDrags { false };
-+    Optional<WebCore::SelectionData> m_dragSelectionData;
 +    OptionSet<WebCore::DragOperation> m_dragSourceOperationMask;
 +    int m_dragEventsQueued = 0;
 +    WebCore::IntPoint m_lastMousePositionForDrag;
+#endif
+#if PLATFORM(GTK) || PLATFORM(WPE)
+    Optional<WebCore::SelectionData> m_dragSelectionData;
+#endif
+#if PLATFORM(WIN)
+    Optional<WebCore::DragDataMap> m_dragSelectionData;
 +#endif
 #endif
 
     PageLoadState m_pageLoadState;
-@@ -2888,6 +2917,9 @@ private:
+@@ -2888,6 +2927,9 @@ private:
         RefPtr<API::Object> messageBody;
     };
     Vector<InjectedBundleMessage> m_pendingInjectedBundleMessages;
@ -15123,7 +15327,7 @@ index 0df616b76fb75033ef20179fe5b296f28355e3e1..d17c19d01c9c5cc44f668dc94ab1d0c1
 #if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
     std::unique_ptr<WebDeviceOrientationUpdateProviderProxy> m_webDeviceOrientationUpdateProviderProxy;
 diff --git a/Source/WebKit/UIProcess/WebPageProxy.messages.in b/Source/WebKit/UIProcess/WebPageProxy.messages.in
-index ef9327d8f6ee7d3fec6527fa52a0b0dc71f397a1..ec0b01c090c02b382448cd44f3eb55f9c88b5876 100644
+index ef9327d8f6ee7d3fec6527fa52a0b0dc71f397a1..8fe26679da1bf27a577c9aea1bca223910a7078f 100644
 --- a/Source/WebKit/UIProcess/WebPageProxy.messages.in
 +++ b/Source/WebKit/UIProcess/WebPageProxy.messages.in
@@ -29,6 +29,7 @@ messages -> WebPageProxy {
@ -15142,7 +15346,7 @@ index ef9327d8f6ee7d3fec6527fa52a0b0dc71f397a1..ec0b01c090c02b382448cd44f3eb55f9
     PluginScaleFactorDidChange(double zoomFactor)
     PluginZoomFactorDidChange(double zoomFactor)
 
-@@ -320,7 +322,7 @@ messages -> WebPageProxy {
+@@ -320,10 +322,12 @@ messages -> WebPageProxy {
     StartDrag(struct WebCore::DragItem dragItem, WebKit::ShareableBitmap::Handle dragImage)
     SetPromisedDataForImage(String pasteboardName, WebKit::SharedMemory::IPCHandle imageHandle, String filename, String extension, String title, String url, String visibleURL, WebKit::SharedMemory::IPCHandle archiveHandle)
 #endif
@ -15150,7 +15354,13 @@ index ef9327d8f6ee7d3fec6527fa52a0b0dc71f397a1..ec0b01c090c02b382448cd44f3eb55f9
 +#if (PLATFORM(GTK) || PLATFORM(WPE)) && ENABLE(DRAG_SUPPORT)
     StartDrag(WebCore::SelectionData selectionData, OptionSet<WebCore::DragOperation> dragOperationMask, WebKit::ShareableBitmap::Handle dragImage)
 #endif
- 
+-
+#if PLATFORM(WIN) && ENABLE(DRAG_SUPPORT)
+    StartDrag(HashMap<unsigned, Vector<String>> dragDataMap)
+#endif
+ #if ENABLE(DRAG_SUPPORT)
+     DidPerformDragOperation(bool handled)
+ #endif
 diff --git a/Source/WebKit/UIProcess/WebProcessPool.cpp b/Source/WebKit/UIProcess/WebProcessPool.cpp
 index 7383e302a7352b6f3b719c84bb531a8b4cd8fea9..a06038e67388689cd11e7ee3082e153bab2d2788 100644
 --- a/Source/WebKit/UIProcess/WebProcessPool.cpp
@ -17332,7 +17542,7 @@ index fec0feefd553d6ec22c4d8cddf9a8ec7fe18fddb..8a2889454afaca72b67793d64093560d
 {
     if (m_page.activeOpenPanelResultListener())
 diff --git a/Source/WebKit/WebProcess/WebCoreSupport/WebDragClient.cpp b/Source/WebKit/WebProcess/WebCoreSupport/WebDragClient.cpp
-index 2eb0886f13ed035a53b8eaa60605de4dfe53fbe3..1c22f9d0451b0d09e1955cb5581174a8f650046b 100644
+index 2eb0886f13ed035a53b8eaa60605de4dfe53fbe3..c46393209cb4f80704bbc9268fad4371347d5b30 100644
 --- a/Source/WebKit/WebProcess/WebCoreSupport/WebDragClient.cpp
 +++ b/Source/WebKit/WebProcess/WebCoreSupport/WebDragClient.cpp
@@ -29,6 +29,13 @@
@ -17354,7 +17564,7 @@ index 2eb0886f13ed035a53b8eaa60605de4dfe53fbe3..1c22f9d0451b0d09e1955cb5581174a8
 }
 
 -#if !PLATFORM(COCOA) && !PLATFORM(GTK)
-+#if !PLATFORM(COCOA) && !PLATFORM(GTK) && !PLATFORM(WPE)
+#if !PLATFORM(COCOA) && !PLATFORM(GTK) && !PLATFORM(WPE) && !PLATFORM(WIN)
 void WebDragClient::startDrag(DragItem, DataTransfer&, Frame&)
 {
 }
@ -17376,6 +17586,70 @@ index b0b4f573b051af835f6568427a5fb8459410acf7..5cd875e631ee27a63ad906ac5155cb20
 }
 
 void WebFrameLoaderClient::didRestoreFromBackForwardCache()
+diff --git a/Source/WebKit/WebProcess/WebCoreSupport/win/WebDragClientWin.cpp b/Source/WebKit/WebProcess/WebCoreSupport/win/WebDragClientWin.cpp
+new file mode 100644
+index 0000000000000000000000000000000000000000..2606914d22e85affd9b2f71c361c9db3a14da4f3
+--- /dev/null
+++ b/Source/WebKit/WebProcess/WebCoreSupport/win/WebDragClientWin.cpp
+@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2011 Igalia S.L.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "WebDragClient.h"
+
+#if ENABLE(DRAG_SUPPORT)
+
+//#include "ArgumentCodersWPE.h"
+#include "ShareableBitmap.h"
+#include "WebPage.h"
+#include "WebPageProxyMessages.h"
+#include <WebCore/DataTransfer.h>
+#include <WebCore/DragData.h>
+#include <WebCore/Pasteboard.h>
+#include <wtf/win/GDIObject.h>
+#include <WebCore/Frame.h>
+
+//#include <WebCore/SelectionData.h>
+
+namespace WebKit {
+using namespace WebCore;
+
+void WebDragClient::didConcludeEditDrag()
+{
+}
+
+void WebDragClient::startDrag(DragItem, DataTransfer& dataTransfer, Frame& frame)
+{
+    m_page->willStartDrag();
+    m_page->send(Messages::WebPageProxy::StartDrag(dataTransfer.pasteboard().createDragDataMap()));
+}
+
+}; // namespace WebKit.
+
+#endif // ENABLE(DRAG_SUPPORT)
 diff --git a/Source/WebKit/WebProcess/WebCoreSupport/wpe/WebDragClientWPE.cpp b/Source/WebKit/WebProcess/WebCoreSupport/wpe/WebDragClientWPE.cpp
 new file mode 100644
 index 0000000000000000000000000000000000000000..9b413bb8150a1633d29b6e2606127c9c1d02442b