Remove reference counting from media::Demuxer and friends.

media/base/filter_collection.cc

Index: media/base/filter_collection.cc
diff --git a/media/base/filter_collection.cc b/media/base/filter_collection.cc
index 911edd5832cd6150b57283af53f80eeed9df8f9a..cee47b990295345d290a5255441db08a1cc80b96 100644
--- a/media/base/filter_collection.cc
+++ b/media/base/filter_collection.cc
@@ -4,7 +4,6 @@
 
 #include "media/base/filter_collection.h"
 
-#include "base/logging.h"
 #include "media/base/audio_renderer.h"
 #include "media/base/demuxer.h"
 #include "media/base/video_renderer.h"
@@ -15,12 +14,12 @@ FilterCollection::FilterCollection() {}
 
 FilterCollection::~FilterCollection() {}
 
-void FilterCollection::SetDemuxer(const scoped_refptr<Demuxer>& demuxer) {
-  demuxer_ = demuxer;
+void FilterCollection::SetDemuxer(scoped_ptr<Demuxer> demuxer) {
+  demuxer_ = demuxer.Pass();
 }
 
-const scoped_refptr<Demuxer>& FilterCollection::GetDemuxer() {
-  return demuxer_;
+scoped_ptr<Demuxer> FilterCollection::GetDemuxer() {
+  return demuxer_.Pass();
 }
 
 void FilterCollection::SetAudioRenderer(