Replace MessageLoopProxy with SingleThreadTaskRunner for media/filters/ + associated code.

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 defe0137d4b9da703136b07861f0ef8dd921145b..968d4c4e115b7b9efb606d0503cd9bf88ad812d3 100644
--- a/media/filters/decrypting_audio_decoder.h
+++ b/media/filters/decrypting_audio_decoder.h
@@ -15,7 +15,7 @@
 #include "media/base/demuxer_stream.h"
 
 namespace base {
-class MessageLoopProxy;
+class SingleThreadTaskRunner;
 }
 
 namespace media {
@@ -26,7 +26,7 @@ class Decryptor;
 
 // Decryptor-based AudioDecoder implementation that can decrypt and decode
 // encrypted audio buffers and return decrypted and decompressed audio frames.
-// All public APIs and callbacks are trampolined to the |message_loop_| so
+// All public APIs and callbacks are trampolined to the |task_runner_| so
 // that no locks are required for thread safety.
 class MEDIA_EXPORT DecryptingAudioDecoder : public AudioDecoder {
  public:
@@ -38,7 +38,7 @@ class MEDIA_EXPORT DecryptingAudioDecoder : public AudioDecoder {
   static const int kSupportedBitsPerChannel;
 
   DecryptingAudioDecoder(
-      const scoped_refptr<base::MessageLoopProxy>& message_loop,
+      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
       const SetDecryptorReadyCB& set_decryptor_ready_cb);
   virtual ~DecryptingAudioDecoder();
 
@@ -105,7 +105,7 @@ class MEDIA_EXPORT DecryptingAudioDecoder : public AudioDecoder {
   // renderer always receives continuous frames without gaps and overlaps.
   void EnqueueFrames(const Decryptor::AudioBuffers& frames);
 
-  scoped_refptr<base::MessageLoopProxy> message_loop_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   base::WeakPtrFactory<DecryptingAudioDecoder> weak_factory_;
   base::WeakPtr<DecryptingAudioDecoder> weak_this_;