Move ProtocolExtensionManager from SessionConnector into its own class

remoting/webapp/crd/js/client_plugin_impl.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.
 
 /**
  * @fileoverview
  * Class that wraps low-level details of interacting with the client plugin.
  *
  * This abstracts a <embed> element and controls the plugin which does
  * the actual remoting work. It also handles differences between
@@ skipping 75 matching lines @@
   /** @param {Event} event Message event from the plugin. */
   this.plugin_.addEventListener('message', function(event) {
       that.handleMessage_(
           /** @type {remoting.ClientPluginMessage} */ (event.data));
     }, false);
 
   if (remoting.settings.CLIENT_PLUGIN_TYPE == 'native') {
     window.setTimeout(this.showPluginForClickToPlay_.bind(this), 500);
   }
 
+  /** @private */
   this.hostDesktop_ = new remoting.ClientPlugin.HostDesktopImpl(
       this, this.postMessage_.bind(this));
 
+  /** @private */
+  this.extensions_ = new remoting.ProtocolExtensionManager(
+      this.sendClientMessage.bind(this));
+
   /** @private {remoting.CredentialsProvider} */
   this.credentials_ = null;
 
   /** @private {string} */
   this.keyRemappings_ = '';
 };
 
 /**
  * Creates plugin element without adding it to a container.
  *
@@ skipping 110 matching lines @@
 
     } else if (message.method == 'logDebugMessage') {
       handler.onDebugMessage(base.getStringAttr(message.data, 'message'));
 
     } else if (message.method == 'onConnectionStatus') {
       var state = remoting.ClientSession.State.fromString(
           base.getStringAttr(message.data, 'state'));
       var error = remoting.ClientSession.ConnectionError.fromString(
           base.getStringAttr(message.data, 'error'));
       handler.onConnectionStatusUpdate(state, error);
-
+      // TODO(kelvinp): Refactor the ClientSession.State into its own file as

[garykac, 2015/04/07 22:14:16]

Or have an onConnected, onDisconnected,... message instead of just
onConnectionStatus.

[kelvinp, 2015/04/08 00:26:02]

Even if we break onConnectionStatus into OnConnected, etc, we still need to
compare the status against some predefined enum string. 
The problem here is that the enum string is defined in ClientSession, which is a
much concept that belongs to a higher layer than the plugin.

+      // the plugin should not depend on ClientSession.
+      if (state === remoting.ClientSession.State.CONNECTED) {
+        this.extensions_.start();
+      }
     } else if (message.method == 'onRouteChanged') {
       var channel = base.getStringAttr(message.data, 'channel');
       var connectionType = base.getStringAttr(message.data, 'connectionType');
       handler.onRouteChanged(channel, connectionType);
 
     } else if (message.method == 'onConnectionReady') {
       var ready = base.getBooleanAttr(message.data, 'ready');
       handler.onConnectionReady(ready);
 
     } else if (message.method == 'setCapabilities') {
       /** @type {!Array<string>} */
       var capabilities = tokenize(
           base.getStringAttr(message.data, 'capabilities'));
       handler.onSetCapabilities(capabilities);
 
     } else if (message.method == 'extensionMessage') {
       var extMsgType = base.getStringAttr(message.data, 'type');
       var extMsgData = base.getStringAttr(message.data, 'data');
-      handler.onExtensionMessage(extMsgType, extMsgData);
+      this.extensions_.onProtocolExtensionMessage(extMsgType, extMsgData);

[garykac, 2015/04/07 22:14:16]

Since this no longer requires a connectionEventHandler, it should be moved out
of this if().

[kelvinp, 2015/04/08 00:26:02]

Done.

     }
   }
 
   if (message.method == 'hello') {
     // Resize in case we had to enlarge it to support click-to-play.
     this.hidePluginForClickToPlay_();
     this.pluginApiVersion_ = base.getNumberAttr(message.data, 'apiVersion');
     this.pluginApiMinVersion_ =
         base.getNumberAttr(message.data, 'apiMinVersion');
 
@@ skipping 117 matching lines @@
 };
 
 /**
  * Deletes the plugin.
  */
 remoting.ClientPluginImpl.prototype.dispose = function() {
   if (this.plugin_) {
     this.plugin_.parentNode.removeChild(this.plugin_);
     this.plugin_ = null;
   }
+
+  base.dispose(this.extensions_);
+  this.extensions_ = null;
 };
 
 /**
  * @return {HTMLEmbedElement} HTML element that corresponds to the plugin.
  */
 remoting.ClientPluginImpl.prototype.element = function() {
   return this.plugin_;
 };
 
 /**
@@ skipping 388 matching lines @@
   this.plugin_.postMessage(JSON.stringify(
       { method: 'extensionMessage',
         data: { type: type, data: message } }));
 
 };
 
 remoting.ClientPluginImpl.prototype.hostDesktop = function() {
   return this.hostDesktop_;
 };
 
+remoting.ClientPluginImpl.prototype.extensions = function() {
+  return this.extensions_;
+};
+
 /**
  * If we haven't yet received a "hello" message from the plugin, change its
  * size so that the user can confirm it if click-to-play is enabled, or can
  * see the "this plugin is disabled" message if it is actually disabled.
  * @private
  */
 remoting.ClientPluginImpl.prototype.showPluginForClickToPlay_ = function() {
   if (!this.helloReceived_) {
     var width = 200;
     var height = 200;
@@ skipping 52 matching lines @@
 remoting.DefaultClientPluginFactory.prototype.preloadPlugin = function() {
   if (remoting.settings.CLIENT_PLUGIN_TYPE != 'pnacl') {
     return;
   }
 
   var plugin = remoting.ClientPluginImpl.createPluginElement_();
   plugin.addEventListener(
       'loadend', function() { document.body.removeChild(plugin); }, false);
   document.body.appendChild(plugin);
 };