[Editing][DOM][CodeHealth] Make Node::isContentEditable and Node::isRichEditable global functions.

third_party/WebKit/Source/core/page/DragController.cpp

 /*
  * Copyright (C) 2007, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Google Inc.
  *
  * 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
@@ skipping 700 matching lines @@
 static Image* getImage(Element* element)
 {
     ASSERT(element);
     ImageResource* cachedImage = getImageResource(element);
     return (cachedImage && !cachedImage->errorOccurred()) ?
         cachedImage->getImage() : nullptr;
 }
 
 static void prepareDataTransferForImageDrag(LocalFrame* source, DataTransfer* dataTransfer, Element* node, const KURL& linkURL, const KURL& imageURL, const String& label)
 {
-    if (node->isContentRichlyEditable()) {
+    if (isContentRichlyEditable(*node)) {
         Range* range = source->document()->createRange();
         range->selectNode(node, ASSERT_NO_EXCEPTION);
         source->selection().setSelection(VisibleSelection(EphemeralRange(range)));
     }
     dataTransfer->declareAndWriteDragImage(node, !linkURL.isEmpty() ? linkURL : imageURL, label);
 }
 
 bool DragController::populateDragDataTransfer(LocalFrame* src, const DragState& state, const IntPoint& dragOrigin)
 {
     ASSERT(dragTypeIsValid(state.m_dragType));
@@ skipping 264 matching lines @@
 
 DEFINE_TRACE(DragController)
 {
     visitor->trace(m_page);
     visitor->trace(m_documentUnderMouse);
     visitor->trace(m_dragInitiator);
     visitor->trace(m_fileInputElementUnderMouse);
 }
 
 } // namespace blink