Fix shutdown crash when WebMediaPlayerImpl is destroyed after RenderViewImpl is.

webkit/glue/webmediaplayer_impl.h

 // Copyright (c) 2011 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.
 
 // Delegate calls from WebCore::MediaPlayerPrivate to Chrome's video player.
 // It contains PipelineImpl which is the actual media player pipeline, it glues
 // the media player pipeline, data source, audio renderer and renderer.
 // PipelineImpl would creates multiple threads and access some public methods
 // of this class, so we need to be extra careful about concurrent access of
 // methods and members.
@@ skipping 87 matching lines @@
   // 5. Null audio renderer
   // The video renderer provided by this class is using the graphics context
   // provided by WebKit to perform renderering. The simple data source does
   // resource loading by loading the whole resource object into memory. Null
   // audio renderer is a fake audio device that plays silence. Provider of the
   // |collection| can override the default filters by adding extra filters to
   // |collection| before calling this method.
   //
   // Callers must call |Initialize()| before they can use the object.
   WebMediaPlayerImpl(WebKit::WebMediaPlayerClient* client,
-                     WebMediaPlayerDelegate* delegate,
+                     base::WeakPtr<WebMediaPlayerDelegate> delegate,
                      media::FilterCollection* collection,
                      media::MessageLoopFactory* message_loop_factory,
                      MediaStreamClient* media_stream_client,
                      media::MediaLog* media_log);
   virtual ~WebMediaPlayerImpl();
 
   // Finalizes initialization of the object.
   bool Initialize(
       WebKit::WebFrame* frame,
       bool use_simple_data_source,
@@ skipping 133 matching lines @@
 
   // Seek gets pending if another seek is in progress. Only last pending seek
   // will have effect.
   bool pending_seek_;
   float pending_seek_seconds_;
 
   WebKit::WebMediaPlayerClient* client_;
 
   scoped_refptr<WebMediaPlayerProxy> proxy_;
 
-  WebMediaPlayerDelegate* delegate_;
+  base::WeakPtr<WebMediaPlayerDelegate> delegate_;
 
   MediaStreamClient* media_stream_client_;
 
 #if WEBKIT_USING_CG
   scoped_ptr<skia::PlatformCanvas> skia_canvas_;
 #endif
 
   scoped_refptr<media::MediaLog> media_log_;
 
   bool incremented_externally_allocated_memory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerImpl);
 };
 
 }  // namespace webkit_glue
 
 #endif  // WEBKIT_GLUE_WEBMEDIAPLAYER_IMPL_H_