Fixed drag and drop into and out of Browser Plugin.

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
 // BrowserPluginGuestManager, which creates and manages the lifetime of the new
 // guest.
 
 #ifndef CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_EMBEDDER_H_
 #define CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_EMBEDDER_H_
 
 #include <map>
 
+#include "base/memory/weak_ptr.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_observer.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebDragOperation.h"
 
 struct BrowserPluginHostMsg_CreateGuest_Params;
 struct BrowserPluginHostMsg_ResizeGuest_Params;
 
 namespace gfx {
 class Point;
 }
 
 namespace content {
 
+class BrowserPluginGuest;
 class BrowserPluginGuestManager;
 class BrowserPluginHostFactory;
 class WebContentsImpl;
 
 class CONTENT_EXPORT BrowserPluginEmbedder : public WebContentsObserver {
  public:
   virtual ~BrowserPluginEmbedder();
 
   static BrowserPluginEmbedder* Create(WebContentsImpl* web_contents);
 
   // Returns the RenderViewHost at a point (|x|, |y|) asynchronously via
   // |callback|. We need a roundtrip to renderer process to get this
   // information.
   void GetRenderViewHostAtPosition(
       int x,
       int y,
       const WebContents::GetRenderViewHostCallback& callback);
 
   // Overrides factory for testing. Default (NULL) value indicates regular
   // (non-test) environment.
   static void set_factory_for_testing(BrowserPluginHostFactory* factory) {
     factory_ = factory;
   }
 
   // WebContentsObserver implementation.
   virtual void RenderViewGone(base::TerminationStatus status) OVERRIDE;
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+  virtual void SystemDragEnded() OVERRIDE;
+
+  void DragSourceEndedAt(int client_x, int client_y, int screen_x,
+      int screen_y, WebKit::WebDragOperation operation);
+
+  void DragSourceMovedTo(int client_x, int client_y,
+                         int screen_x, int screen_y);
+
+  void OnUpdateDragCursor(bool* handled);
+
+  void DragEnteredGuest(BrowserPluginGuest* guest);
+
+  void DragLeftGuest(BrowserPluginGuest* guest);
+
+  void StartDrag(BrowserPluginGuest* guest);
+
+  void StopDrag(BrowserPluginGuest* guest);
 
  private:
   friend class TestBrowserPluginEmbedder;
 
   BrowserPluginEmbedder(WebContentsImpl* web_contents);
 
   void CleanUp();
 
   BrowserPluginGuestManager* GetBrowserPluginGuestManager();
 
@@ skipping 12 matching lines @@
   static BrowserPluginHostFactory* factory_;
 
   // Map that contains outstanding queries to |GetRenderViewHostAtPosition|.
   // We need a roundtrip to the renderer process to retrieve the answer,
   // so we store these callbacks until we hear back from the renderer.
   typedef std::map<int, WebContents::GetRenderViewHostCallback>
       GetRenderViewHostCallbackMap;
   GetRenderViewHostCallbackMap pending_get_render_view_callbacks_;
   // Next request id for BrowserPluginMsg_PluginAtPositionRequest query.
   int next_get_render_view_request_id_;
+  base::WeakPtr<BrowserPluginGuest> guest_dragging_over_;

[Fady Samuel, 2013/04/18 21:22:41]

Could you please add comments over these two pointers as to what they're used
for?

Could you also add a TODO(fsamuel) along with a crbug to investigate whether
it's possible avoid guest_dragging_over_.

[mthiesse, 2013/04/19 14:55:49]

Done.

+  base::WeakPtr<BrowserPluginGuest> guest_started_drag_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPluginEmbedder);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_EMBEDDER_H_