Browser Plugin: Simplified guest attachment

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.
 
 // This module implements Webview (<webview>) as a custom element that wraps a
 // BrowserPlugin object element. The object element is hidden within
 // the shadow DOM of the Webview element.
 
 var DocumentNatives = requireNative('document_natives');
 var EventBindings = require('event_bindings');
@@ skipping 147 matching lines @@
 
 // Implemented when the experimental API is available.
 WebViewInternal.maybeRegisterExperimentalAPIs = function(proto) {}
 
 /**
  * @constructor
  */
 function WebViewInternal(webviewNode) {
   privates(webviewNode).internal = this;
   this.webviewNode = webviewNode;
+  this.attached = false;
   this.browserPluginNode = this.createBrowserPluginNode();
   var shadowRoot = this.webviewNode.createShadowRoot();
   shadowRoot.appendChild(this.browserPluginNode);
 
   this.setupWebviewNodeAttributes();
   this.setupFocusPropagation();
   this.setupWebviewNodeProperties();
   this.setupWebviewNodeEvents();
 }
 
@@ skipping 384 matching lines @@
 };
 
 /**
  * @private
  */
 WebViewInternal.prototype.setupWebviewNodeEvents = function() {
   var self = this;
   this.viewInstanceId = IdGenerator.GetNextId();
   var onInstanceIdAllocated = function(e) {
     var detail = e.detail ? JSON.parse(e.detail) : {};
-    self.instanceId = detail.windowId;
-    var params = {
-      'api': 'webview',
-      'instanceId': self.viewInstanceId
-    };
-    if (self.userAgentOverride) {
-      params['userAgentOverride'] = self.userAgentOverride;
-    }
-    self.browserPluginNode['-internal-attach'](params);
-
-    var events = self.getEvents();
-    for (var eventName in events) {
-      self.setupEvent(eventName, events[eventName]);
-    }
+    self.attachWindow(detail.windowId);

[lazyboy, 2014/04/23 20:42:07]

nit: probably self.attachWindowAndSetUpEvents() is better.

   };
   this.browserPluginNode.addEventListener('-internal-instanceid-allocated',
                                           onInstanceIdAllocated);
   this.setupWebRequestEvents();
   this.setupExperimentalContextMenus_();
 
   this.on = {};
   var events = self.getEvents();
   for (var eventName in events) {
     this.setupEventProperty(eventName);
@@ skipping 206 matching lines @@
     attach: function(webview) {
       validateCall();
       if (!webview)
         throw new Error(ERROR_MSG_WEBVIEW_EXPECTED);
       // Attach happens asynchronously to give the tagWatcher an opportunity
       // to pick up the new webview before attach operates on it, if it hasn't
       // been attached to the DOM already.
       // Note: Any subsequent errors cannot be exceptions because they happen
       // asynchronously.
       setTimeout(function() {
-        var attached =
-            browserPluginNode['-internal-attachWindowTo'](webview,
-                                                          event.windowId);
+        var attached = false;
+        var webViewInternal = privates(webview).internal;
+        if (webViewInternal instanceof WebViewInternal) {
+          attached = webViewInternal.attachWindow(event.windowId);
+        }
+
         if (!attached) {
           window.console.error(ERROR_MSG_NEWWINDOW_UNABLE_TO_ATTACH);
         }
         // If the object being passed into attach is not a valid <webview>
         // then we will fail and it will be treated as if the new window
         // was rejected. The permission API plumbing is used here to clean
         // up the state created for the new window if attaching fails.
         WebView.setPermission(
             self.instanceId, requestId, attached ? 'allow' : 'deny');
       }, 0);
@@ skipping 190 matching lines @@
 WebViewInternal.prototype.setUserAgentOverride = function(userAgentOverride) {
   this.userAgentOverride = userAgentOverride;
   if (!this.instanceId) {
     // If we are not attached yet, then we will pick up the user agent on
     // attachment.
     return;
   }
   WebView.overrideUserAgent(this.instanceId, userAgentOverride);
 };
 
+/** @private */
+WebViewInternal.prototype.attachWindow = function(instanceId) {
+  if (this.attached) {
+    return false;
+  }
+  this.attached = true;
+  this.instanceId = instanceId;
+  var params = {
+    'api': 'webview',
+    'instanceId': this.viewInstanceId
+  };
+  if (this.userAgentOverride) {
+    params['userAgentOverride'] = this.userAgentOverride;
+  }
+  this.browserPluginNode['-internal-attach'](this.instanceId, params);
+
+  var events = this.getEvents();
+  for (var eventName in events) {
+    this.setupEvent(eventName, events[eventName]);
+  }
+  return true;
+};
+
 // Registers browser plugin <object> custom element.
 function registerBrowserPluginElement() {
   var proto = Object.create(HTMLObjectElement.prototype);
 
   proto.createdCallback = function() {
     this.setAttribute('type', 'application/browser-plugin');
     // The <object> node fills in the <webview> container.
     this.style.width = '100%';
     this.style.height = '100%';
   };
@@ skipping 144 matching lines @@
 
 /**
  * Implemented when the experimental API is available.
  * @private
  */
 WebViewInternal.prototype.setupExperimentalContextMenus_ = function() {};
 
 exports.WebView = WebView;
 exports.WebViewInternal = WebViewInternal;
 exports.CreateEvent = CreateEvent;