MediaResource refactoring to support multiple streams

media/base/media_url_demuxer.cc

Index: media/base/media_url_demuxer.cc
diff --git a/media/base/media_url_demuxer.cc b/media/base/media_url_demuxer.cc
index 755e91023be2fbc209e69ee71a1f4d9fc7ebb0fd..08d5e6b197ee1629b4df98888e61d49f47ad1dd8 100644
--- a/media/base/media_url_demuxer.cc
+++ b/media/base/media_url_demuxer.cc
@@ -17,18 +17,18 @@ MediaUrlDemuxer::MediaUrlDemuxer(
 
 MediaUrlDemuxer::~MediaUrlDemuxer() {}
 
-// Should never be called since DemuxerStreamProvider::Type is URL.
-DemuxerStream* MediaUrlDemuxer::GetStream(DemuxerStream::Type type) {
+// Should never be called since MediaResource::Type is URL.
+std::vector<DemuxerStream*> MediaUrlDemuxer::GetStreams() {
   NOTREACHED();
-  return nullptr;
+  return std::vector<DemuxerStream*>();
 }
 
 MediaUrlParams MediaUrlDemuxer::GetMediaUrlParams() const {
   return params_;
 }
 
-DemuxerStreamProvider::Type MediaUrlDemuxer::GetType() const {
-  return DemuxerStreamProvider::Type::URL;
+MediaResource::Type MediaUrlDemuxer::GetType() const {
+  return MediaResource::Type::URL;
 }
 
 std::string MediaUrlDemuxer::GetDisplayName() const {