Fix spurious selections marker layer update to avoid extra render

spec/text-editor-component-spec.js

@@ -34,12 +34,6 @@ describe('TextEditorComponent', () => {
   it('renders lines and line numbers for the visible region', async () => {
     const {component, element, editor} = buildComponent({rowsPerTile: 3})
 
-    // TODO: An extra update is caused by marker layer events being asynchronous,
-    // so the cursor getting added triggers an update even though we created
-    // the component after this occurred. We should make marker layer events
-    // synchronous and batched on the transaction.
-    await component.getNextUpdatePromise()
-
     expect(element.querySelectorAll('.line-number').length).toBe(13)
     expect(element.querySelectorAll('.line').length).toBe(13)
 

src/text-editor.coffee

@@ -210,7 +210,7 @@ class TextEditor extends Model
     if @cursors.length is 0 and not suppressCursorCreation
       initialLine = Math.max(parseInt(initialLine) or 0, 0)
       initialColumn = Math.max(parseInt(initialColumn) or 0, 0)
-      @addCursorAtBufferPosition([initialLine, initialColumn])
+      @addCursorAtBufferPosition([initialLine, initialColumn], {suppressLayerUpdateEvent: true})
 
     @languageMode = new LanguageMode(this)
 
@@ -2140,7 +2140,7 @@ class TextEditor extends Model
   #
   # Returns a {Cursor}.
   addCursorAtBufferPosition: (bufferPosition, options) ->
-    @selectionsMarkerLayer.markBufferPosition(bufferPosition, {invalidate: 'never'})
+    @selectionsMarkerLayer.markBufferPosition(bufferPosition, Object.assign({invalidate: 'never'}, options))
     @getLastSelection().cursor.autoscroll() unless options?.autoscroll is false
     @getLastSelection().cursor