WeakPtr destruction order cleanup: media edition.

media/cast/video_sender/video_sender.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 MEDIA_CAST_VIDEO_SENDER_VIDEO_SENDER_H_
 #define MEDIA_CAST_VIDEO_SENDER_VIDEO_SENDER_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 123 matching lines @@
   // with a video frame. The key is the lowest 8 bits of frame id (which is
   // what is sent via RTCP). This map is used for logging purposes. The only
   // time when this mapping will be incorrect is when it receives an ACK for a
   // old enough frame such that 8-bit wrap around has already occurred, which
   // should be pretty rare.
   RtpTimestamp frame_id_to_rtp_timestamp_[256];
 
   bool initialized_;
   // Indicator for receiver acknowledgments.
   bool active_session_;
+
+  // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<VideoSender> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoSender);
 };
 
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_VIDEO_SENDER_VIDEO_SENDER_H_