Add media router common classes and unittests.

chrome/browser/media/router/media_route.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_ROUTE_H_
+#define CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTE_H_
+
+#include <string>
+
+#include "base/gtest_prod_util.h"
+#include "base/logging.h"
+#include "base/values.h"
+#include "chrome/browser/media/router/media_route_id.h"
+#include "chrome/browser/media/router/media_sink.h"
+#include "chrome/browser/media/router/media_source.h"
+#include "url/gurl.h"
+
+namespace media_router {
+
+using RouteRequestId = int64;
+
+class MediaRouteFactory;
+
+// For now, a simple transition graph: NEW -> CONNECTED -> CLOSED.
+enum MediaRouteState {
+  // The route is new and not yet connected to a sink.
+  MEDIA_ROUTE_STATE_NEW,
+  // The route is active and connected to a sink.
+  MEDIA_ROUTE_STATE_CONNECTED,
+  // The route has been disconnected.
+  MEDIA_ROUTE_STATE_CLOSED
+};
+
+// MediaRoute objects contain the status and metadata of a routing
+// operation. The fields are immutable and reflect the route status
+// only at the time of object creation. Updated route statuses must
+// be retrieved as new MediaRoute objects from the Media Router.
+struct MediaRoute {

[xhwang, 2015/03/09 17:37:31]

For struct, you should make the member variables public and drop the accessors.
Now I just realized you want to make the class immutable. Also you have an
Equals() function. With that, maybe a "class" is the right option. Sorry for
going back and forth on this.

[Kevin M, 2015/03/09 23:32:06]

Done.

+ public:
+  ~MediaRoute();
+
+  // The media route identifier.
+  const MediaRouteId& media_route_id() const { return media_route_id_; }
+
+  // The state of the media route.
+  MediaRouteState state() const { return state_; }
+
+  // The media source being routed.
+  const MediaSource& media_source() const { return media_source_; }
+
+  // The ID of the sink being routed to.
+  const MediaSinkId& sink_id() const { return sink_id_; }
+
+  // The description of the media route activity, for example
+  // "Playing Foo Bar Music All Access."
+  // TODO(kmarshall): Do we need to pass locale for bidi rendering?
+  const std::string& description() const { return description_; }
+
+  // Returns |true| if the route is created locally (versus discovered
+  // by a media route provider.)
+  bool is_local() const { return is_local_; }
+
+  bool Equals(const MediaRoute& other) const;
+
+ private:
+  friend class MediaRouteFactory;
+  FRIEND_TEST_ALL_PREFIXES(MediaRouteTest, Equals);

[xhwang, 2015/03/09 17:37:31]

It seems MediaRouteTest is not accessing any private stuff. Not needed?

[Kevin M, 2015/03/09 23:32:06]

Done.

+
+  MediaRoute(const MediaRouteId& media_route_id,
+             const MediaSource& media_source,
+             const MediaSinkId& sink_id,
+             const std::string& description,
+             bool is_local);
+
+  const MediaRouteId media_route_id_;
+  const MediaSource media_source_;
+  const MediaSinkId sink_id_;
+  const std::string description_;
+  const bool is_local_;
+  const MediaRouteState state_;
+};
+
+}  // namespace media_router
+
+#endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_ROUTE_H_