WeakPtr destruction order cleanup: media edition.

media/audio/alsa/alsa_output.h

Index: media/audio/alsa/alsa_output.h
diff --git a/media/audio/alsa/alsa_output.h b/media/audio/alsa/alsa_output.h
index 65a23f751247fd2d7e4a5afb7f5442e5fb204c9d..4645cf5308f189347071b5046fff423f98a5e677 100644
--- a/media/audio/alsa/alsa_output.h
+++ b/media/audio/alsa/alsa_output.h
@@ -201,10 +201,6 @@ class MEDIA_EXPORT AlsaPcmOutputStream : public AudioOutputStream {
   scoped_ptr<media::SeekableBuffer> buffer_;
   uint32 frames_per_packet_;
 
-  // Allows us to run tasks on the AlsaPcmOutputStream instance which are
-  // bound by its lifetime.
-  base::WeakPtrFactory<AlsaPcmOutputStream> weak_factory_;
-
   InternalState state_;
   float volume_;  // Volume level from 0.0 to 1.0.
 
@@ -217,6 +213,10 @@ class MEDIA_EXPORT AlsaPcmOutputStream : public AudioOutputStream {
   scoped_ptr<ChannelMixer> channel_mixer_;
   scoped_ptr<AudioBus> mixed_audio_bus_;
 
+  // NOTE: This must always be last so it's invalidated before other member
+  // variables might be accessed.
+  base::WeakPtrFactory<AlsaPcmOutputStream> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(AlsaPcmOutputStream);
 };