Add Media Router Mojo impl code.

chrome/browser/media/router/media_router.h

Index: chrome/browser/media/router/media_router.h
diff --git a/chrome/browser/media/router/media_router.h b/chrome/browser/media/router/media_router.h
index 3acee0fe8dc2a7839a9b252cc2d3699f45f73340..580c1ce2b71ca80baa645d872fa3b0e8041e7843 100644
--- a/chrome/browser/media/router/media_router.h
+++ b/chrome/browser/media/router/media_router.h
@@ -9,6 +9,7 @@
 #include <vector>
 
 #include "base/callback.h"
+#include "chrome/browser/media/router/issue.h"
 #include "chrome/browser/media/router/media_route.h"
 #include "chrome/browser/media/router/media_route_id.h"
 #include "chrome/browser/media/router/media_sink.h"
@@ -16,10 +17,11 @@
 
 namespace media_router {
 
+class IssuesObserver;
 class MediaRoutesObserver;
 class MediaSinksObserver;
 
-// Type of callback used in |RequestRoute()|. Callback is invoked when the
+// Type of callback used in |CreateRoute()|. Callback is invoked when the
 // route request either succeeded or failed.
 // The first argument is the route created. If the route request failed, this
 // will be a nullptr.
@@ -38,9 +40,9 @@ class MediaRouter {
 
   // Requests a media route from |source| to |sink_id|.
   // |callback| is invoked with a response indicating success or failure.
-  virtual void RequestRoute(const MediaSourceId& source,
-                            const MediaSinkId& sink_id,
-                            const MediaRouteResponseCallback& callback) = 0;
+  virtual void CreateRoute(const MediaSourceId& source,
+                           const MediaSinkId& sink_id,
+                           const MediaRouteResponseCallback& callback) = 0;
 
   // Closes the media route specified by |route_id|.
   virtual void CloseRoute(const MediaRouteId& route_id) = 0;
@@ -51,6 +53,9 @@ class MediaRouter {
   virtual void PostMessage(const MediaRouteId& route_id,
                            const std::string& message) = 0;
 
+  // Clears the issue with the id |issue_id|.
+  virtual void ClearIssue(const Issue::IssueId& issue_id) = 0;
+
   // Receives updates from a MediaRouter instance.
   class Delegate {
    public:
@@ -59,13 +64,25 @@ class MediaRouter {
     // |message|: The message.
     virtual void OnMessage(const MediaRouteId& route_id,
                            const std::string& message) = 0;
+
+    // Called when there is an issue.
+    // |issue|: The issue.
+    virtual void OnIssue(const Issue& issue) = 0;
   };
 
- protected:
+  // Adds the IssuesObserver |observer|.

[mark a. foltz, 2015/05/08 00:58:37]

Why are there two APIs for callers to be notified about Issues?

IssueObserver and MediaRouter::Delegate::OnIssue

Can we eliminate one?

[Kevin M, 2015/05/12 23:56:09]

Yes, OnIssue is redundant. Removed.

+  virtual void AddIssuesObserver(IssuesObserver* observer) = 0;
+
+  // Removes the IssuesObserver |observer|.
+  virtual void RemoveIssuesObserver(IssuesObserver* observer) = 0;
+
+ private:
+  friend class IssuesObserver;
   friend class MediaSinksObserver;
   friend class MediaRoutesObserver;
+  friend class MediaRouterImpl;

[mark a. foltz, 2015/05/08 00:58:37]

The implementation should not be friended by the interface (how does this not
create a circular dependency).

Is there some API that needs to be protected: ?

[Kevin M, 2015/05/12 23:56:09]

Removed.

The friend relationship existed to allow MediaRouterMojoImpl to allow
MediaRouterImpl to pass calls to MediaRouterImpl::Register*Observer to the
MediaRouterMojoImpl object.

It's no longer necessary now that MediaRouterImpl is gone.

 
-  // The following APIs are called by MediaSinksObserver/MediaRoutesObserver
+  // The following APIs are called by the friend observer classes

[mark a. foltz, 2015/05/08 00:58:37]

I think I would prefer listing the classes specifically.

[Kevin M, 2015/05/12 23:56:09]

Done.

   // and implementations of MediaRouter only.
 
   // Registers |observer| with this MediaRouter. |observer| specifies a media