[Media Router] Merge createMediaRouteController and setMediaRouteStatusObserver in bindings

chrome/renderer/resources/extensions/media_router_bindings.js

Index: chrome/renderer/resources/extensions/media_router_bindings.js
diff --git a/chrome/renderer/resources/extensions/media_router_bindings.js b/chrome/renderer/resources/extensions/media_router_bindings.js
index 24b7f15ee546108c383b49a429d2cc5b32a6b5bc..51d97a16e9b5c30cf78ab7ce9cb753d2102ee302 100644
--- a/chrome/renderer/resources/extensions/media_router_bindings.js
+++ b/chrome/renderer/resources/extensions/media_router_bindings.js
@@ -919,40 +919,33 @@ define('media_router_bindings', [
 
   /**
    * Creates a controller for the given route and binds the given
-   * InterfaceRequest to it.
+   * InterfaceRequest to it, and registers an observer for media status updates
+   * for the route.
    * @param {string} routeId
    * @param {!bindings.InterfaceRequest} controllerRequest
+   * @param {!mediaStatusMojom.MediaStatusObserverPtr} observer
    * @return {!Promise<!{success: boolean}>} Resolves to true if a controller
    *     is created. Resolves to false if a controller cannot be created, or if
    *     the controller is already bound.
    */
   MediaRouteProvider.prototype.createMediaRouteController = function(
-      routeId, controllerRequest) {
+      routeId, controllerRequest, observer) {
     // TODO(imcheng): Remove this check when M59 is in stable.

[imcheng, 2017/04/21 21:25:15]

s/59/60

[takumif, 2017/04/21 23:01:11]

Done.

-    if (!this.handlers_.createMediaRouteController) {
+    if (!this.handlers_.createMediaRouteController ||

[imcheng, 2017/04/21 21:25:15]

It probably makes sense to use a combined API in the component as well, so as to
minimize the logic that is handled by the bindings code. 

[takumif, 2017/04/21 23:01:11]

Done.

+        !this.handlers_.setMediaRouteStatusObserver) {
       return Promise.resolve({success: false});
     }
 
     this.handlers_.onBeforeInvokeHandler();
-    this.handlers_.createMediaRouteController(routeId, controllerRequest)
-        .then(controller => {success: true},
-              e => {success: false});
-  }
-
-  /**
-   * Sets the MediaStatus oberver for a given route. MediaStatus updates are
-   * notified via the given observer interface.
-   * @param {string} routeId
-   * @param {!mediaStatusMojom.MediaStatusObserverPtr} observer
-   */
-  MediaRouteProvider.prototype.setMediaRouteStatusObserver = function(
-      routeId, observer) {
-    // TODO(imcheng): Remove this check when M59 is in stable.
-    if (!this.handlers_.setMediaRouteStatusObserver) {
-      return;
-    }
-    this.handlers_.onBeforeInvokeHandler();
-    this.handlers_.setMediaRouteStatusObserver(routeId, observer);
+    const result =
+        this.handlers_.createMediaRouteController(routeId, controllerRequest)
+            .then(controller => {
+                    this.handlers_.setMediaRouteStatusObserver(routeId,
+                                                               observer);
+                    return {success: true};
+                  },
+                  e => {success: false});
+    return result;
   };
 
   mediaRouter = new MediaRouter(new mediaRouterMojom.MediaRouterPtr(