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 5d9c4da243580620650c3a5083a8d6dcc64b1eef..d801078c1ab023d8a9f311da8881f1f0959e7cac 100644
--- a/media/filters/decrypting_audio_decoder.h
+++ b/media/filters/decrypting_audio_decoder.h
@@ -108,8 +108,6 @@ 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_;
 
@@ -146,6 +144,11 @@ class MEDIA_EXPORT DecryptingAudioDecoder : public AudioDecoder {
 
   scoped_ptr<AudioTimestampHelper> timestamp_helper_;
 
+  // NOTE: These must always be last so they're invalidated before other member
+  // variables might be accessed.
+  base::WeakPtr<DecryptingAudioDecoder> weak_this_;
+  base::WeakPtrFactory<DecryptingAudioDecoder> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(DecryptingAudioDecoder);
 };