Add media router common classes and unittests.

chrome/browser/media/router/media_sink.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_SINK_H_
+#define CHROME_BROWSER_MEDIA_ROUTER_MEDIA_SINK_H_
+
+#include <string>
+
+#include "chrome/browser/media/router/media_route_id.h"
+
+namespace media_router {
+
+using MediaSinkId = std::string;
+
+// Represents a sink to which media can be routed.
+class MediaSink {

[xhwang, 2015/03/05 22:28:50]

ditto: should this be a struct?

[Kevin M, 2015/03/06 23:12:45]

Done.

+ public:
+  // |sink_id|: Unique identifier for the MediaSink.
+  // |name|: Descriptive name of the MediaSink.
+  // |status|: Current status of the MediaSink.

[xhwang, 2015/03/05 22:28:50]

There's no |status| in the constructor.

[Kevin M, 2015/03/06 23:12:45]

Done.

+  MediaSink(const MediaSinkId& sink_id,
+            const std::string& name);
+  ~MediaSink();
+
+  const MediaSinkId& sink_id() const { return sink_id_; }
+  const std::string& name() const { return name_; }
+  std::string StatusAsString() const;

[xhwang, 2015/03/05 22:28:50]

This is not defined? Remove or define it?

[Kevin M, 2015/03/06 23:12:45]

Done.

+
+  bool operator==(const MediaSink& other) const;
+  bool operator!=(const MediaSink& other) const;

[xhwang, 2015/03/05 22:28:50]

ditto about operator overloading...

[Kevin M, 2015/03/06 23:12:45]

Done.

+
+ private:
+  const MediaSinkId sink_id_;
+  const std::string name_;
+};
+
+}  // namespace media_router
+
+#endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_SINK_H_