<webview>: Partially migrate loadcommit event from content to chrome

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.
 
 var watchForTag = require('tagWatcher').watchForTag;
+var eventBindings = require('event_bindings');
 
 /** @type {Array.<string>} */
 var WEB_VIEW_ATTRIBUTES = ['name', 'src', 'partition', 'autosize', 'minheight',
     'minwidth', 'maxheight', 'maxwidth'];
 
 
 // All exposed api methods for <webview>, these are forwarded to the browser
 // plugin.
 var WEB_VIEW_API_METHODS = [
   'back',
@@ skipping 15 matching lines @@
   'loadabort' : ['url', 'isTopLevel', 'reason'],
   'loadcommit' : ['url', 'isTopLevel'],
   'loadredirect' : ['oldUrl', 'newUrl', 'isTopLevel'],
   'loadstart' : ['url', 'isTopLevel'],
   'loadstop' : [],
   'responsive' : ['processId'],
   'sizechanged': ['oldHeight', 'oldWidth', 'newHeight', 'newWidth'],
   'unresponsive' : ['processId']
 };
 
+var createEvent = function(name) {
+  var eventOpts = { supportsListeners: true, supportsFilters: true };

[lazyboy, 2013/06/19 19:22:16]

nit: here and below: no space after { and before }

[Fady Samuel, 2013/06/19 19:42:11]

Done.

+  return new eventBindings.Event('webview.on' + name, undefined, eventOpts);
+};
+
+var loadCommitEvent = createEvent('loadcommit');
+
 window.addEventListener('DOMContentLoaded', function() {
   watchForTag('WEBVIEW', function(addedNode) { new WebView(addedNode); });
 });
 
 /**
  * @constructor
  */
 function WebView(webviewNode) {
   this.webviewNode_ = webviewNode;
   this.browserPluginNode_ = this.createBrowserPluginNode_();
@@ skipping 189 matching lines @@
     if (newValue != oldValue) {
       this.webviewNode_.setAttribute(mutation.attributeName, newValue);
     }
   }
 };
 
 /**
  * @private
  */
 WebView.prototype.setupWebviewNodeEvents_ = function() {
+  var webviewNode = this.webviewNode_;
+  // TODO(fsamuel): Generalize this further as we add more events.
+  var onAttached = function(e) {
+    var detail = e.detail ? JSON.parse(e.detail) : {};
+    loadCommitEvent.addListener(function(event) {

[lazyboy, 2013/06/19 19:22:16]

How is it ensured that loadcommit event doesn't reach here (and therefore be
ignored) before attach event?

[Fady Samuel, 2013/06/19 19:42:11]

No content is loaded prior to attachment. We fire the -internal-attach prior to
sending the IPC to the browser process to attach. The IPC to add an event
listener gets sent prior to the IPC to attach as well.

+      var evt = new Event('loadcommit', { bubbles: true });

[lazyboy, 2013/06/19 19:22:16]

e event evt are kind of hard to read here.
s/evt/webviewEvent

[Fady Samuel, 2013/06/19 19:42:11]

Done.

+      var attribs = WEB_VIEW_EVENTS['loadcommit'];
+      $Array.forEach(attribs, function(attribName) {
+        evt[attribName] = event[attribName];
+      });
+      webviewNode.dispatchEvent(evt);
+    }, { instanceId: detail.windowId });
+  };
+  this.browserPluginNode_.addEventListener('-internal-attached', onAttached);
+
   for (var eventName in WEB_VIEW_EVENTS) {
     this.setupEvent_(eventName, WEB_VIEW_EVENTS[eventName]);
   }
   this.setupNewWindowEvent_();
   this.setupPermissionEvent_();
 };
 
 /**
  * @private
  */
@@ skipping 207 matching lines @@
   return [];
 };
 
 /**
  * Implemented when the experimental API is available.
  * @private
  */
 WebView.prototype.maybeSetupExperimentalAPI_ = function() {};
 
 exports.WebView = WebView;