WeakPtr destruction order cleanup: media edition.

content/renderer/media/buffered_data_source.h

 // Copyright 2013 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_MEDIA_BUFFERED_DATA_SOURCE_H_
 #define CONTENT_RENDERER_MEDIA_BUFFERED_DATA_SOURCE_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 198 matching lines @@
   // Current playback rate.
   float playback_rate_;
 
   // Buffered byte ranges awaiting set_host() being called to report to host().
   media::Ranges<int64> queued_buffered_byte_ranges_;
 
   scoped_refptr<media::MediaLog> media_log_;
 
   DownloadingCB downloading_cb_;
 
+  // NOTE: This must always be last so it's invalidated before other member
+  // variables might be accessed.
   base::WeakPtrFactory<BufferedDataSource> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BufferedDataSource);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_BUFFERED_DATA_SOURCE_H_