[Media Router] Adds return value to mojo MediaRouteProvider::TerminateRoute.

extensions/renderer/resources/media_router_bindings.js

Index: extensions/renderer/resources/media_router_bindings.js
diff --git a/extensions/renderer/resources/media_router_bindings.js b/extensions/renderer/resources/media_router_bindings.js
index 86ea2173273d3493db74a10456731a3f580ef5a0..e94d252d71f4705d1712a79aa1cd88fde85dec0a 100644
--- a/extensions/renderer/resources/media_router_bindings.js
+++ b/extensions/renderer/resources/media_router_bindings.js
@@ -153,10 +153,8 @@ define('media_router_bindings', [
    * @return {!mediaRouterMojom.RouteRequestResultCode}
    */
   function getRouteRequestResultCode_(error) {
-    if (error.message.startsWith('timeout'))
-      return mediaRouterMojom.RouteRequestResultCode.TIMED_OUT;
-    else
-      return mediaRouterMojom.RouteRequestResultCode.UNKNOWN_ERROR;
+    return error.errorCode ? error.errorCode :
+      mediaRouterMojom.RouteRequestResultCode.UNKNOWN_ERROR;
   }
 
   /**
@@ -172,13 +170,13 @@ define('media_router_bindings', [
   }
 
   /**
-   * Creates and returns a error route response from given Error object
+   * Creates and returns a error route response from given Error object.
    * @param {!Error} error
    * @return {!Object}
    */
   function toErrorRouteResponse_(error) {
     return {
-        error_text: 'Error creating route: ' + error.message,
+        error_text: error.message,
         result_code: getRouteRequestResultCode_(error)
     };
   }
@@ -677,7 +675,18 @@ define('media_router_bindings', [
    * @param {!string} routeId

[imcheng, 2016/07/15 20:18:45]

I think this should return a Promise - see createRoute.

@return !Promise<!Object> Resolved to the result of terminating the route.

Or something similar.

[mark a. foltz, 2016/07/15 20:36:49]

Done.

    */
   MediaRouteProvider.prototype.terminateRoute = function(routeId) {
-    this.handlers_.terminateRoute(routeId);
+    // TODO(crbug.com/627967): Remove code path that doesn't expect a Promise
+    // in M56.
+    var maybePromise = this.handlers_.terminateRoute(routeId);
+    var successResult = {result_code: RouteRequestResultCode.OK};
+    if (maybePromise) {
+      maybePromise.then(

[imcheng, 2016/07/15 20:18:45]

return maybePromise.then(...

[mark a. foltz, 2016/07/15 20:36:49]

Good catch. Done.

+        function() { return successResult; },
+        function(err) { return toErrorRouteResponse_(err); }
+      );
+    } else {
+      return successResult;

[imcheng, 2016/07/15 20:18:45]

return Promise.resolve(successResult);

[mark a. foltz, 2016/07/15 20:36:49]

Done.

+    }
   };
 
   /**