Make WebView work with either enteredViewCallback or attachedCallback.

chrome/renderer/resources/extensions/web_view.js

 // Copyright (c) 2012 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.
 
 // Shim that simulates a <webview> tag via Mutation Observers.
 //
 // The actual tag is implemented via the browser plugin. The internals of this
 // are hidden via Shadow DOM.
 
 'use strict';
@@ skipping 916 matching lines @@
   };
 
   proto.attributeChangedCallback = function(name, oldValue, newValue) {
     if (!this.internal_) {
       return;
     }
     var internal = this.internal_(secret);
     internal.handleBrowserPluginAttributeMutation_(name, newValue);
   };
 
-  proto.enteredViewCallback = function() {
+  proto.attachedCallback = function() {
     // Load the plugin immediately.
     var unused = this.nonExistentAttribute;
   };
 
+  // TODO(dominicc): Remove this line once Custom Elements renames
+  // enteredViewCallback to attachedCallback
+  proto.enteredViewCallback = proto.attachedCallback;
+
   WebViewInternal.BrowserPlugin =
       DocumentNatives.RegisterElement('browser-plugin', {extends: 'object',
                                                          prototype: proto});
 
   delete proto.createdCallback;
+  delete proto.attachedCallback;
+  delete proto.detachedCallback;
+  delete proto.attributeChangedCallback;
+
+  // TODO(dominicc): Remove these lines once Custom Elements renames
+  // enteredView, leftView callbacks to attached, detached
+  // respectively.
   delete proto.enteredViewCallback;
   delete proto.leftViewCallback;
-  delete proto.attributeChangedCallback;
 }
 
 // Registers <webview> custom element.
 function registerWebViewElement() {
   var proto = Object.create(HTMLElement.prototype);
 
   proto.createdCallback = function() {
     new WebViewInternal(this);
   };
 
@@ skipping 48 matching lines @@
     $Function.apply(internal.insertCSS_, internal, arguments);
   };
   WebViewInternal.maybeRegisterExperimentalAPIs(proto, secret);
 
   window.WebView =
       DocumentNatives.RegisterElement('webview', {prototype: proto});
 
   // Delete the callbacks so developers cannot call them and produce unexpected
   // behavior.
   delete proto.createdCallback;
+  delete proto.attachedCallback;
+  delete proto.detachedCallback;
+  delete proto.attributeChangedCallback;
+
+  // TODO(dominicc): Remove these lines once Custom Elements renames
+  // enteredView, leftView callbacks to attached, detached
+  // respectively.
   delete proto.enteredViewCallback;
   delete proto.leftViewCallback;
-  delete proto.attributeChangedCallback;
 }
 
 var useCapture = true;
 window.addEventListener('readystatechange', function listener(event) {
   if (document.readyState == 'loading')
     return;
 
   registerBrowserPluginElement();
   registerWebViewElement();
   window.removeEventListener(event.type, listener, useCapture);
@@ skipping 15 matching lines @@
  * Implemented when the experimental API is available.
  * @private
  */
 WebViewInternal.prototype.maybeGetExperimentalPermissions_ = function() {
   return [];
 };
 
 exports.WebView = WebView;
 exports.WebViewInternal = WebViewInternal;
 exports.CreateEvent = CreateEvent;