Remove MessageLoop methods from Filter interface

media/filters/decoder_base.h

Index: media/filters/decoder_base.h
diff --git a/media/filters/decoder_base.h b/media/filters/decoder_base.h
index f8b26abb645bfbc903a44e6e218bd66b4fa68091..7b72d44b8b6fea65d24b932471138f6eea0d5205 100644
--- a/media/filters/decoder_base.h
+++ b/media/filters/decoder_base.h
@@ -26,7 +26,6 @@ namespace media {
 template <class Decoder, class Output>
 class DecoderBase : public Decoder {
  public:
-
   // Filter implementation.
   virtual void Stop(FilterCallback* callback) {
     this->message_loop()->PostTask(
@@ -62,9 +61,12 @@ class DecoderBase : public Decoder {
         NewRunnableMethod(this, &DecoderBase::ReadTask, output));
   }
 
+  MessageLoop* message_loop() { return message_loop_; }
+
  protected:
-  DecoderBase()
-      : pending_reads_(0),
+  explicit DecoderBase(MessageLoop* message_loop)
+      : message_loop_(message_loop),
+        pending_reads_(0),
         pending_requests_(0),
         state_(kUninitialized) {
   }
@@ -274,6 +276,8 @@ class DecoderBase : public Decoder {
     return true;
   }
 
+  MessageLoop* message_loop_;
+
   // Tracks the number of asynchronous reads issued to |demuxer_stream_|.
   // Using size_t since it is always compared against deque::size().
   size_t pending_reads_;