Let PaintAtAck send an int tag instead of the TransportDIB handle.

chrome/browser/renderer_host/render_widget_host.h

 // Copyright (c) 2009 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.
 
 #ifndef CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_H_
 #define CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_H_
 
 #include <deque>
 #include <string>
 #include <vector>
@@ skipping 204 matching lines @@
   // This tells the renderer to paint into a bitmap and return it,
   // regardless of whether the tab is hidden or not.  It resizes the
   // web widget to match the |page_size| and then returns the bitmap
   // scaled so it matches the |desired_size|, so that the scaling
   // happens on the rendering thread.  When the bitmap is ready, the
   // renderer sends a PaintAtSizeACK to this host, and the painting
   // observer is notified.  Note that this bypasses most of the update
   // logic that is normally invoked, and doesn't put the results into
   // the backing store.
   void PaintAtSize(TransportDIB::Handle dib_handle,
+                   int tag,
                    const gfx::Size& page_size,
                    const gfx::Size& desired_size);
 
   // Get access to the widget's backing store.  If a resize is in progress,
   // then the current size of the backing store may be less than the size of
   // the widget's view.  If you pass |force_create| as true, then the backing
   // store will be created if it doesn't exist. Otherwise, NULL will be returned
   // if the backing store doesn't already exist. It will also return NULL if the
   // backing store could not be created.
   BackingStore* GetBackingStore(bool force_create);
@@ skipping 234 matching lines @@
   // Called if we know the renderer is responsive. When we currently think the
   // renderer is unresponsive, this will clear that state and call
   // NotifyRendererResponsive.
   void RendererIsResponsive();
 
   // IPC message handlers
   void OnMsgRenderViewReady();
   void OnMsgRenderViewGone();
   void OnMsgClose();
   void OnMsgRequestMove(const gfx::Rect& pos);
-  void OnMsgPaintAtSizeAck(const TransportDIB::Handle& dib_handle,
-                           const gfx::Size& size);
+  void OnMsgPaintAtSizeAck(int tag, const gfx::Size& size);
   void OnMsgUpdateRect(const ViewHostMsg_UpdateRect_Params& params);
   void OnMsgCreateVideo(const gfx::Size& size);
   void OnMsgUpdateVideo(TransportDIB::Id bitmap, const gfx::Rect& bitmap_rect);
   void OnMsgDestroyVideo();
   void OnMsgInputEventAck(const IPC::Message& message);
   void OnMsgFocus();
   void OnMsgBlur();
 
   void OnMsgSetCursor(const WebCursor& cursor);
   void OnMsgImeUpdateTextInputState(WebKit::WebTextInputType type,
@@ skipping 205 matching lines @@
   // we don't do it more than once.
   bool requested_accessibility_tree_;
 
   // Optional video YUV layer for used for out-of-process compositing.
   scoped_ptr<VideoLayer> video_layer_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHost);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_H_