Fix a crash when saving a <canvas> or <img> image which is large.

content/renderer/render_view_impl.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.
 
 #ifndef CONTENT_RENDERER_RENDER_VIEW_IMPL_H_
 #define CONTENT_RENDERER_RENDER_VIEW_IMPL_H_
 
 #include <deque>
 #include <map>
 #include <set>
@@ skipping 360 matching lines @@
                                      const blink::WebWindowFeatures& features,
                                      const blink::WebString& frame_name,
                                      blink::WebNavigationPolicy policy,
                                      bool suppress_opener);
   virtual blink::WebWidget* createPopupMenu(blink::WebPopupType popup_type);
   virtual blink::WebStorageNamespace* createSessionStorageNamespace();
   virtual void printPage(blink::WebLocalFrame* frame);
   virtual bool enumerateChosenDirectory(
       const blink::WebString& path,
       blink::WebFileChooserCompletion* chooser_completion);
+  virtual void saveImageFromDataURL(const blink::WebString& data_url);
   virtual void didCancelCompositionOnSelectionChange();
   virtual bool handleCurrentKeyboardEvent();
   virtual bool runFileChooser(
       const blink::WebFileChooserParams& params,
       blink::WebFileChooserCompletion* chooser_completion);
   virtual void showValidationMessage(const blink::WebRect& anchor_in_root_view,
                                      const blink::WebString& main_text,
                                      const blink::WebString& sub_text,
                                      blink::WebTextDirection hint) OVERRIDE;
   virtual void hideValidationMessage() OVERRIDE;
@@ skipping 737 matching lines @@
   // use the Observer interface to filter IPC messages and receive frame change
   // notifications.
   // ---------------------------------------------------------------------------
 
   DISALLOW_COPY_AND_ASSIGN(RenderViewImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_VIEW_IMPL_H_