WeakPtr destruction order cleanup: media edition.

media/cast/audio_receiver/audio_receiver.h

Index: media/cast/audio_receiver/audio_receiver.h
diff --git a/media/cast/audio_receiver/audio_receiver.h b/media/cast/audio_receiver/audio_receiver.h
index 2742399f33a8a4b5a2ed64da63d412663b09465d..6270498b6a4b54d9f4a9e1f3817644c50d08c9fe 100644
--- a/media/cast/audio_receiver/audio_receiver.h
+++ b/media/cast/audio_receiver/audio_receiver.h
@@ -123,8 +123,6 @@ class AudioReceiver : public base::NonThreadSafe,
   // Processes raw audio events to be sent over to the cast sender via RTCP.
   ReceiverRtcpEventSubscriber event_subscriber_;
 
-  base::WeakPtrFactory<AudioReceiver> weak_factory_;
-
   const transport::AudioCodec codec_;
   const int frequency_;
   base::TimeDelta target_delay_delta_;
@@ -148,6 +146,9 @@ class AudioReceiver : public base::NonThreadSafe,
   // it allows the event to be transmitted via RTCP.
   RtpTimestamp frame_id_to_rtp_timestamp_[256];
 
+  // NOTE: Weak pointers must be invalidated before all other member variables.
+  base::WeakPtrFactory<AudioReceiver> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(AudioReceiver);
 };