[Media Router] Add a supports_web_ui_controller attribute to MediaRoute

chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js

Index: chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js
diff --git a/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js b/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js
index 6ccebfcc0e9e103e71e11c3ed24f9089986d748e..ecf8ad645ae0b6a6e880b5417e4cb7cd0f3fe1c1 100644
--- a/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js
+++ b/chrome/browser/resources/media_router/elements/media_router_container/media_router_container.js
@@ -389,16 +389,6 @@ Polymer({
       observer: 'updateElementPositioning_',
     },
 
-    /**
-     * Whether the WebUI route controls should be shown instead of the
-     * extensionview in the route details view.
-     * @type {boolean}
-     */
-    useWebUiRouteControls: {
-      type: Boolean,
-      value: false,
-    },
-
     /**
      * Whether the user has explicitly selected a cast mode.
      * @private {boolean}
@@ -1883,8 +1873,7 @@ Polymer({
    * from route details view to the sink list view.
    */
   onRouteControllerInvalidated: function() {
-    if (this.useWebUiRouteControls &&
-        this.currentView_ == media_router.MediaRouterView.ROUTE_DETAILS) {
+    if (this.currentView_ == media_router.MediaRouterView.ROUTE_DETAILS) {
       this.currentRoute_ = null;
       this.showSinkList_();
     }
@@ -2453,7 +2442,7 @@ Polymer({
   showRouteDetails_: function(route) {
     this.currentRoute_ = route;
     this.currentView_ = media_router.MediaRouterView.ROUTE_DETAILS;
-    if (this.useWebUiRouteControls) {
+    if (route.supportsWebUiController) {
       media_router.browserApi.onMediaControllerAvailable(route.id);
     }
     if (this.$$('route-details')) {