Improve <webview> autosize:

content/renderer/browser_plugin/browser_plugin.h

 // Copyright 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_BROWSER_PLUGIN_BROWSER_PLUGIN_H_
 #define  CONTENT_RENDERER_BROWSER_PLUGIN_BROWSER_PLUGIN_H_
 
 #include "third_party/WebKit/public/web/WebPlugin.h"
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 337 matching lines @@
   scoped_refptr<BrowserPluginCompositingHelper> compositing_helper_;
 
   // Used to identify the plugin to WebBindings.
   scoped_ptr<struct _NPP> npp_;
 
   // Weak factory used in v8 |MakeWeak| callback, since the v8 callback might
   // get called after BrowserPlugin has been destroyed.
   base::WeakPtrFactory<BrowserPlugin> weak_ptr_factory_;
 
   std::vector<EditCommand> edit_commands_;
+  // This helps keep track if we need to expand damage buffer.
+  gfx::Size last_seen_auto_view_size_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPlugin);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_BROWSER_PLUGIN_BROWSER_PLUGIN_H_