Drag-and-drop: Move startDrag out of WebView/RenderView.

third_party/WebKit/Source/web/ChromeClientImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 242 matching lines @@
 bool ChromeClientImpl::hadFormInteraction() const {
   return m_webView->pageImportanceSignals() &&
          m_webView->pageImportanceSignals()->hadFormInteraction();
 }
 
 void ChromeClientImpl::startDragging(LocalFrame* frame,
                                      const WebDragData& dragData,
                                      WebDragOperationsMask mask,
                                      const WebImage& dragImage,
                                      const WebPoint& dragImageOffset) {
-  m_webView->startDragging(frame, dragData, mask, dragImage, dragImageOffset);
+  WebLocalFrameImpl* webFrame = WebLocalFrameImpl::fromFrame(frame);
+  WebFrameWidgetBase* frameWidget = webFrame->localRoot()->frameWidget();
+  if (!frameWidget || !frameWidget->client())

[dcheng, 2016/11/07 21:11:00]

Nit: do we need to null-check client or widget here? I'd like to understand how
we can get to this code with either of these being null.

[paulmeyer, 2016/11/07 22:18:13]

Probably not. Removed.

+    return;
+
+  WebReferrerPolicy policy = webFrame->document().referrerPolicy();
+  m_webView->setDoingDragAndDrop(true);
+  frameWidget->client()->startDragging(policy, dragData, mask, dragImage,
+                                       dragImageOffset);
 }
 
 bool ChromeClientImpl::acceptsLoadDrops() const {
   return !m_webView->client() || m_webView->client()->acceptsLoadDrops();
 }
 
 namespace {
 
 void updatePolicyForEvent(const WebInputEvent* inputEvent,
                           NavigationPolicy* policy) {
@@ skipping 881 matching lines @@
   if (RuntimeEnabledFeatures::presentationEnabled())
     PresentationController::provideTo(frame, client->presentationClient());
   if (RuntimeEnabledFeatures::audioOutputDevicesEnabled())
     provideAudioOutputDeviceClientTo(frame,
                                      AudioOutputDeviceClientImpl::create());
   if (RuntimeEnabledFeatures::installedAppEnabled())
     InstalledAppController::provideTo(frame, client->installedAppClient());
 }
 
 }  // namespace blink