Pass origin to StartObservingMediaSinks.

chrome/browser/media/router/media_source.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_MEDIA_ROUTER_MEDIA_SOURCE_H_
 #define CHROME_BROWSER_MEDIA_ROUTER_MEDIA_SOURCE_H_
 
 #include <stddef.h>
 
 #include <ostream>
 #include <string>
 
 #include "base/hash.h"
 
 namespace media_router {
 
 
 class MediaSource {
  public:
   using Id = std::string;
 
   explicit MediaSource(const MediaSource::Id& id);
   MediaSource();
   ~MediaSource();
 
   // Gets the ID of the media source.
   MediaSource::Id id() const;
 
+  // Gets the origin of the media source.
+  std::string origin() const;
+
+  // Sets the origin of the media source.
+  void set_origin(std::string origin);
+
   // Returns true if two MediaSource objects use the same media ID.
   bool Equals(const MediaSource& other) const;
 
   // Returns true if a MediaSource is empty or uninitialized.
   bool Empty() const;
 
   // Used for logging.
   std::string ToString() const;
 
-  // Hash operator for hash containers.
-  struct Hash {
-    size_t operator()(const MediaSource& source) const {
-      return base::Hash(source.id());
-    }
-  };
+  bool operator==(const MediaSource& other) const;
+  bool operator<(const MediaSource& other) const;
 
  private:
   MediaSource::Id id_;
+  std::string origin_;
 };
 
 }  // namespace media_router
 
+namespace std {
+template <> struct hash<media_router::MediaSource> {
+    size_t operator () (const media_router::MediaSource &m) const {
+      return base::HashInts32(base::Hash(m.id()),
+                              base::Hash(m.origin()));
+    }
+};
+}
+
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_SOURCE_H_