Add never option to scrollbar settings

assets/settings/default.json

@@ -53,6 +53,8 @@
   //    "system"
   // 3. Always show the scrollbar:
   //    "always"
+  // 4. Never show the scrollbar:
+  //    "never"
   "show_scrollbars": "auto",
   // Whether the screen sharing icon is shown in the os status bar.
   "show_call_status_icon": true,

crates/editor/src/element.rs

@@ -2064,6 +2064,7 @@ impl Element<Editor> for EditorElement {
             }
             settings::ShowScrollbars::System => editor.scroll_manager.scrollbars_visible(),
             settings::ShowScrollbars::Always => true,
+            settings::ShowScrollbars::Never => false,
         };
 
         let include_root = editor

crates/settings/src/settings.rs

@@ -76,6 +76,7 @@ pub enum ShowScrollbars {
     Auto,
     System,
     Always,
+    Never,
 }
 
 #[derive(Copy, Clone, Debug, Serialize, Deserialize, JsonSchema, PartialEq, Eq, Default)]