remoting: Fix JSCompiler issues blocking ES6 transition.

remoting/webapp/base/js/ipc.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
 * @fileoverview
 *
 * In Chrome Apps, some platform APIs can only be called from the background
 * page (e.g. reloading a chrome.app.AppWindow).  Likewise, some chrome API's
 * must be initiated by user interaction, which can only be called from the
@@ skipping 128 matching lines @@
   }
 };
 
 /**
  * Invokes a method on a remote page
  *
  * @param {string} methodName
  * @param {...} var_args
  * @return {Promise} A Promise that would resolve to the return value of the
  *   handler or reject if the handler throws an exception.
+ * @suppress {reportUnknownTypes}
  */
 base.Ipc.invoke = function(methodName, var_args) {
   var params = Array.prototype.slice.call(arguments, 1);
   var sendMessage = base.Promise.as(
       chrome.runtime.sendMessage,
       [null, new base.Ipc.Request_(methodName, params)]);
 
   return sendMessage.then(
     /** @param {?{error: Error}} response */
     function(response) {
@@ skipping 18 matching lines @@
 };
 
 base.Ipc.deleteInstance = function() {
   if (instance_) {
     instance_.dispose_();
     instance_ = null;
   }
 };
 
 })();