[Extensions Bindings] Introduce a supportsLazyListeners property

extensions/renderer/resources/messaging.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.
 
 // chrome.runtime.messaging API implementation.
 // TODO(robwu): Fix this indentation.
 
   // TODO(kalman): factor requiring chrome out of here.
   var chrome = requireNative('chrome').GetChrome();
   var lastError = require('lastError');
   var logActivity = requireNative('activityLogger');
   var logging = requireNative('logging');
   var messagingNatives = requireNative('messaging_natives');
   var processNatives = requireNative('process');
   var utils = require('utils');
   var messagingUtils = require('messaging_utils');
 
   // The reserved channel name for the sendRequest/send(Native)Message APIs.
   // Note: sendRequest is deprecated.
   var kRequestChannel = "chrome.extension.sendRequest";
   var kMessageChannel = "chrome.runtime.sendMessage";
   var kNativeMessageChannel = "chrome.runtime.sendNativeMessage";
   var kPortClosedError = 'Attempting to use a disconnected port object';
 
   var jsEvent;
   function createAnonymousEvent(schema) {
     if (bindingUtil) {
+      var supportsFilters = false;
+      var supportsLazyListeners = false;

[lazyboy, 2017/07/14 00:04:42]

Do we need true here?

[Devlin, 2017/07/14 15:37:54]

Nope, see previous comment.

[lazyboy, 2017/07/17 23:38:50]

Acknowledged.

       // Native custom events ignore schema.
-      var supportsFilters = false;
       return bindingUtil.createCustomEvent(undefined, undefined,
-                                           supportsFilters);
+                                           supportsFilters,
+                                           supportsLazyListeners);
     }
     var options = {
       __proto__: null,
       unmanaged: true,
     };
     if (!jsEvent)
       jsEvent = require('event_bindings').Event;
     return new jsEvent(undefined, schema, options);
   }
 
@@ skipping 422 matching lines @@
 exports.$set('kNativeMessageChannel', kNativeMessageChannel);
 exports.$set('Port', Port);
 exports.$set('createPort', createPort);
 exports.$set('sendMessageImpl', sendMessageImpl);
 exports.$set('sendMessageUpdateArguments', sendMessageUpdateArguments);
 
 // For C++ code to call.
 exports.$set('dispatchOnConnect', dispatchOnConnect);
 exports.$set('dispatchOnDisconnect', dispatchOnDisconnect);
 exports.$set('dispatchOnMessage', dispatchOnMessage);