WeakPtr destruction order cleanup: media edition.

media/filters/decrypting_audio_decoder.h

Index: media/filters/decrypting_audio_decoder.h
diff --git a/media/filters/decrypting_audio_decoder.h b/media/filters/decrypting_audio_decoder.h
index 43e05e24010036fc74f7eaa877d0d69351a2ab7c..4d00ad5d1c5304d3b4ba1554cd3d5c955c169f2b 100644
--- a/media/filters/decrypting_audio_decoder.h
+++ b/media/filters/decrypting_audio_decoder.h
@@ -99,8 +99,6 @@ class MEDIA_EXPORT DecryptingAudioDecoder : public AudioDecoder {
   void EnqueueFrames(const Decryptor::AudioBuffers& frames);
 
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
-  base::WeakPtrFactory<DecryptingAudioDecoder> weak_factory_;
-  base::WeakPtr<DecryptingAudioDecoder> weak_this_;
 
   State state_;
 
@@ -136,6 +134,10 @@ class MEDIA_EXPORT DecryptingAudioDecoder : public AudioDecoder {
 
   scoped_ptr<AudioTimestampHelper> timestamp_helper_;
 
+  // NOTE: Weak pointers must be invalidated before all other member variables.
+  base::WeakPtrFactory<DecryptingAudioDecoder> weak_factory_;
+  base::WeakPtr<DecryptingAudioDecoder> weak_this_;
+
   DISALLOW_COPY_AND_ASSIGN(DecryptingAudioDecoder);
 };