dragend fix for mac <webview>.

content/browser/browser_plugin/browser_plugin_embedder.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // A BrowserPluginEmbedder handles messages coming from a BrowserPlugin's
 // embedder that are not directed at any particular existing guest process.
 // In the beginning, when a BrowserPlugin instance in the embedder renderer
 // process requests an initial navigation, the WebContents for that renderer
 // renderer creates a BrowserPluginEmbedder for itself. The
 // BrowserPluginEmbedder, in turn, forwards the requests to a
@@ skipping 57 matching lines @@
   void SystemDragEnded();
 
   // Used to handle special keyboard events.
   bool HandleKeyboardEvent(const NativeWebKeyboardEvent& event);
 
  private:
   explicit BrowserPluginEmbedder(WebContentsImpl* web_contents);
 
   BrowserPluginGuestManager* GetBrowserPluginGuestManager() const;
 
+  void ClearGuestDragStateIfApplicable();
+
   bool DidSendScreenRectsCallback(WebContents* guest_web_contents);
 
   bool SetZoomLevelCallback(double level, WebContents* guest_web_contents);
 
   bool UnlockMouseIfNecessaryCallback(bool* mouse_unlocked, WebContents* guest);
 
   // Called by the content embedder when a guest exists with the provided
   // |instance_id|.
   void OnGuestCallback(int instance_id,
                        const BrowserPluginHostMsg_Attach_Params& params,
@@ skipping 13 matching lines @@
   // handle a race condition when dropping onto the guest that started the drag
   // (the race is that the dragend message arrives before the drop message so
   // the drop never takes place).
   // crbug.com/233571
   base::WeakPtr<BrowserPluginGuest> guest_dragging_over_;
 
   // Pointer to the guest that started the drag, used to forward necessary drag
   // status messages to the correct guest.
   base::WeakPtr<BrowserPluginGuest> guest_started_drag_;
 
+  // Keeps track of "dragend" state.
+  bool seen_system_drag_ended_;
+  bool seen_drag_source_ended_at_;
+
   base::WeakPtrFactory<BrowserPluginEmbedder> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPluginEmbedder);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_EMBEDDER_H_