Merge pull request rstudio#8542 from rstudio/bugfix/visual-editor-ace…

…-firefox

Fix scroll/focus issue in visual editor in non-Chrome browsers

src/gwt/src/org/rstudio/studio/client/workbench/views/source/editors/text/ace/AceEditorNative.java

@@ -206,6 +206,16 @@ public final native Element getTextInputElement() /*-{
  return this.textInput.getElement();
  }-*/;
 
+ /**
+ * Forces the use of browser focus scrolling. This is the default on Chrome, but on other
+ * browsers, a complicated hack involving setting the 'ace_nocontext' attribute on all parent
+ * elements is used instead to avoid scroll jitter. This is not necessary in embedded editors,
+ * and causes ProseMirror to go nuts (see issue 8518), so this hook allows us to turn it off.
+ */
+ public final native void useBrowserInputFocus() /*-{
+ this.textInput.$focusScroll = "browser";
+ }-*/;
+
  /**
  * Set an aria-label on the input element
  * @param label

src/gwt/src/org/rstudio/studio/client/workbench/views/source/editors/text/visualmode/VisualModeChunk.java

@@ -231,6 +231,9 @@ public FileSystemItem getActiveFile()
  // Prevent tab from advancing into editor
  chunkEditor.getTextInputElement().setTabIndex(-1);
 
+ // Force the use of browser APIs to set focus to the input element
+ chunkEditor.useBrowserInputFocus();
+
  // Allow the editor's size to be determined by its content (these
  // settings trigger an auto-growing behavior), up to a max of 1000
  // lines.