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;
+
+extern const RouteRequestId kInvalidRouteRequestId;
+
+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. The current status of a MediaRoute
+// needs to be pulled from the Media Route Provider Manager, which is the

[mark a. foltz, 2015/03/05 16:58:41]

The MRPM is a component in another process (the extension) so someone writing
code here wouldn't be able to access it directly.  Maybe it would be better to
just say the Media Router here and leave that as an implementation detail?

[Kevin M, 2015/03/05 18:34:18]

Done.

+// source of truth for route information.
+class MediaRoute {
+ 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 information?

[mark a. foltz, 2015/03/05 16:58:41]

pass locale information for bidi rendering?

[Kevin M, 2015/03/05 18:34:18]

Done.

+  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 operator==(const MediaRoute& other) const;
+  bool operator!=(const MediaRoute& other) const;
+
+ private:
+  friend class MediaRouteFactory;
+  FRIEND_TEST_ALL_PREFIXES(MediaRouteTest, Equals);
+
+  // |media_route_id|: Uniquely identifies the route among active
+  // instances for this media source.
+  // |type|: Type of media route.
+  // |media_source|: Description of source of the route.
+  // |sink_id|: ID of the MediaSink of the route.
+  // |description|: Description of the route to be displayed.
+  // |is_local|: true if the route was created from this browser.

[mark a. foltz, 2015/03/05 16:58:41]

Since these parameters map 1:1 to the public and documented getters above, it
should be clear what they mean from context and the individual descriptions can
be omitted.  No harm in leaving it in and I don't feel strongly about it.

[Kevin M, 2015/03/05 18:34:18]

I'll remove it so there's less to keep in sync.

+  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_