[Media Router] Add a supports_web_ui_controller attribute to MediaRoute

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

Index: chrome/browser/resources/media_router/elements/route_details/route_details.js
diff --git a/chrome/browser/resources/media_router/elements/route_details/route_details.js b/chrome/browser/resources/media_router/elements/route_details/route_details.js
index eeaf2a5de7702fdc2b997e2c7c3670c04b3e2c20..bf4e6aec1d6126d3ac6eedb72c1bd71dabfdd237 100644
--- a/chrome/browser/resources/media_router/elements/route_details/route_details.js
+++ b/chrome/browser/resources/media_router/elements/route_details/route_details.js
@@ -33,8 +33,7 @@ Polymer({
      */
     controllerType_: {
       type: Number,
-      computed: 'computeControllerType_(useWebUiRouteControls,' +
-          'isExtensionViewReady)',
+      computed: 'computeControllerType_(route, isExtensionViewReady)',
     },
 
     /**
@@ -95,16 +94,6 @@ Polymer({
       type: Object,
       value: null,
     },
-
-    /**
-     * Whether we should use the WebUI route controls. This value is used for
-     * updating |controllerType_|,
-     * @type {boolean}
-     */
-    useWebUiRouteControls: {
-      type: Boolean,
-      value: false,
-    },
   },
 
   behaviors: [
@@ -161,14 +150,13 @@ Polymer({
   },
 
   /**
-   * @param {boolean} useWebUiRouteControls
+   * @param {?media_router.Route} route
    * @param {boolean} isExtensionViewReady
    * @return {number} An enum value to represent the controller to show.
    * @private
    */
-  computeControllerType_: function(
-      useWebUiRouteControls, isExtensionViewReady) {
-    if (useWebUiRouteControls) {
+  computeControllerType_: function(route, isExtensionViewReady) {
+    if (route && route.supportsWebUiController) {
       return media_router.ControllerType.WEBUI;
     }
     if (isExtensionViewReady) {
@@ -251,6 +239,15 @@ Polymer({
     }
   },
 
+  /**
+   * @param {?media_router.Route} route
+   * @return {boolean}
+   * @private
+   */
+  shouldAttemptLoadingExtensionView_: function(route) {
+    return !!route && !route.supportsWebUiController;

[takumif, 2017/06/19 18:10:28]

The Closure compiler complains that the return type is boolean|null without
this.

[imcheng, 2017/06/19 19:56:13]

Acknowledged.

+  },
+
   /**
    * @param {number} controllerType
    * @return {boolean} Whether the extensionview should be shown instead of the