Die, |that|, die!

This CL cleans up some uses of the "var that = this" paradigm that can be more elegently and efficiently expressed using the |bind| function. Specifically:

var that = this;
f(function(x, y, z) { that.g(x, y, z); });

Is equivalent to:

f(this.g.bind(this));

The latter is shorter, doesn't need explicit JSDoc type annotation, and is more efficient (though I doubt we'll notice any speed-up).

I haven't changed the code to use |bind| where the situation is significantly more complex than the snippet shown above. In theory it would be possible, but I doubt the code would be more readable as a result.

BUG=None
TEST=Manual

Review URL: https://chromiumcodereview.appspot.com/10444041

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@139355 0039d316-1c4b-4281-b951-d872f2087c98

12 files changed, 84 insertions, 157 deletions

diff --git a/remoting/webapp/client_plugin_async.js b/remoting/webapp/client_plugin_async.js
index b016e03..4d128b8 100644
--- a/remoting/webapp/client_plugin_async.js
+++ b/remoting/webapp/client_plugin_async.js
@@ -58,10 +58,7 @@ remoting.ClientPluginAsync = function(plugin) {
   this.plugin.addEventListener('message', function(event) {
       that.handleMessage_(event.data);
     }, false);
-  var showPluginForClickToPlay = function() {
-    that.showPluginForClickToPlay_();
-  };
-  window.setTimeout(showPluginForClickToPlay, 500);
+  window.setTimeout(this.showPluginForClickToPlay_.bind(this), 500);
 };
 
 /**
diff --git a/remoting/webapp/client_plugin_v1.js b/remoting/webapp/client_plugin_v1.js
index 9f9efce..01801e9 100644
--- a/remoting/webapp/client_plugin_v1.js
+++ b/remoting/webapp/client_plugin_v1.js
@@ -40,23 +40,18 @@ remoting.ClientPluginV1 = function(plugin) {
 
   // Connect event handlers.
 
-  /** @type {remoting.ClientPluginV1} */
-  var that = this;
-
   /** @param {string} iq The IQ stanza to send. */
-  this.plugin.sendIq = function(iq) { that.onSendIq_(iq); };
+  this.plugin.sendIq = this.onSendIq_.bind(this);
 
   /** @param {string} msg The message to log. */
-  this.plugin.debugInfo = function(msg) { that.onDebugInfo_(msg); };
+  this.plugin.debugInfo = this.onDebugInfo_.bind(this);
 
   /**
    * @param {number} status The plugin status.
    * @param {number} error The plugin error status, if any.
    */
-  this.plugin.connectionInfoUpdate = function(status, error) {
-    that.onConnectionInfoUpdate_(status, error);
-  };
-  this.plugin.desktopSizeUpdate = function() { that.onDesktopSizeUpdate_(); };
+  this.plugin.connectionInfoUpdate = this.onConnectionInfoUpdate_.bind(this);
+  this.plugin.desktopSizeUpdate = this.onDesktopSizeUpdate_.bind(this);
 };
 
 /**
diff --git a/remoting/webapp/client_session.js b/remoting/webapp/client_session.js
index dfccccd..a25befa 100644
--- a/remoting/webapp/client_session.js
+++ b/remoting/webapp/client_session.js
@@ -60,30 +60,24 @@ remoting.ClientSession = function(hostJid, hostPublicKey, sharedSecret,
   this.logToServer = new remoting.LogToServer();
   this.onStateChange = onStateChange;
 
-  /** @type {number?} */
+  /** @type {number?} @private */
   this.notifyClientDimensionsTimer_ = null;
 
-  /** @type {remoting.ClientSession} */
-  var that = this;
-  /** @type {function():void} @private */
-  this.callPluginLostFocus_ = function() { that.pluginLostFocus_(); };
-  /** @type {function():void} @private */
-  this.callPluginGotFocus_ = function() { that.pluginGotFocus_(); };
-  /** @type {function():void} @private */
-  this.callEnableShrink_ = function() {
-    that.setScaleToFit(true);
-    that.scroll_(0, 0);  // Reset bump-scroll offsets.
-  };
-  /** @type {function():void} @private */
-  this.callDisableShrink_ = function() { that.setScaleToFit(false); };
-  /** @type {function():void} @private */
-  this.callToggleFullScreen_ = function() { that.toggleFullScreen_(); };
-  /** @type {remoting.MenuButton} @private */
+  /** @private */
+  this.callPluginLostFocus_ = this.pluginLostFocus_.bind(this);
+  /** @private */
+  this.callPluginGotFocus_ = this.pluginGotFocus_.bind(this);
+  /** @private */
+  this.callEnableShrink_ = this.setScaleToFit.bind(this, true);
+  /** @private */
+  this.callDisableShrink_ = this.setScaleToFit.bind(this, false);
+  /** @private */
+  this.callToggleFullScreen_ = this.toggleFullScreen_.bind(this);
+  /** @private */
   this.screenOptionsMenu_ = new remoting.MenuButton(
       document.getElementById('screen-options-menu'),
-      function() { that.onShowOptionsMenu_(); }
-  );
-  /** @type {remoting.MenuButton} @private */
+      this.onShowOptionsMenu_.bind(this));
+  /** @private */
   this.sendKeysMenu_ = new remoting.MenuButton(
       document.getElementById('send-keys-menu')
   );
@@ -256,12 +250,9 @@ remoting.ClientSession.prototype.createPluginAndConnect =
 
   this.plugin.element().focus();
 
-  /** @type {remoting.ClientSession} */
-  var that = this;
   /** @param {boolean} result */
-  this.plugin.initialize(function(result) {
-      that.onPluginInitialized_(oauth2AccessToken, result);
-    });
+  this.plugin.initialize(
+      this.onPluginInitialized_.bind(this, oauth2AccessToken));
   this.plugin.element().addEventListener(
       'focus', this.callPluginGotFocus_, false);
   this.plugin.element().addEventListener(
@@ -311,24 +302,17 @@ remoting.ClientSession.prototype.onPluginInitialized_ =
   this.setScaleToFit(this.plugin.hasFeature(
       remoting.ClientPlugin.Feature.HIGH_QUALITY_SCALING));
 
-  /** @type {remoting.ClientSession} */ var that = this;
   /** @param {string} msg The IQ stanza to send. */
-  this.plugin.onOutgoingIqHandler = function(msg) { that.sendIq_(msg); };
+  this.plugin.onOutgoingIqHandler = this.sendIq_.bind(this);
   /** @param {string} msg The message to log. */
   this.plugin.onDebugMessageHandler = function(msg) {
     console.log('plugin: ' + msg);
   };
 
-  /**
-   * @param {number} status The plugin status.
-   * @param {number} error The plugin error status, if any.
-   */
-  this.plugin.onConnectionStatusUpdateHandler = function(status, error) {
-    that.connectionStatusUpdateCallback(status, error);
-  };
-  this.plugin.onDesktopSizeUpdateHandler = function() {
-    that.onDesktopSizeChanged_();
-  };
+  this.plugin.onConnectionStatusUpdateHandler =
+      this.connectionStatusUpdateCallback.bind(this);
+  this.plugin.onDesktopSizeUpdateHandler =
+      this.onDesktopSizeChanged_.bind(this);
 
   this.connectPluginToWcs_(oauth2AccessToken);
 };
@@ -410,6 +394,10 @@ remoting.ClientSession.prototype.sendCtrlAltDel = function() {
 remoting.ClientSession.prototype.setScaleToFit = function(scaleToFit) {
   this.scaleToFit = scaleToFit;
   this.updateDimensions();
+  // If enabling scaling, reset bump-scroll offsets.
+  if (scaleToFit) {
+    this.scroll_(0, 0);
+  }
 }
 
 /**
@@ -480,15 +468,15 @@ remoting.ClientSession.prototype.connectPluginToWcs_ =
     console.error('Tried to connect without a full JID.');
   }
   remoting.formatIq.setJids(this.clientJid, this.hostJid);
-  /** @type {remoting.ClientSession} */
-  var that = this;
+  var plugin = this.plugin;
+  var forwardIq = plugin.onIncomingIq.bind(plugin);
   /** @param {string} stanza The IQ stanza received. */
   var onIncomingIq = function(stanza) {
     console.log(remoting.formatIq.prettifyReceiveIq(stanza));
-    that.plugin.onIncomingIq(stanza);
+    forwardIq(stanza);
   }
   remoting.wcs.setOnIq(onIncomingIq);
-  that.plugin.connect(this.hostJid, this.hostPublicKey, this.clientJid,
+  this.plugin.connect(this.hostJid, this.hostPublicKey, this.clientJid,
                       this.sharedSecret, this.authenticationMethods,
                       this.authenticationTag);
 };
@@ -540,13 +528,11 @@ remoting.ClientSession.prototype.onResize = function() {
 
   // Defer notifying the host of the change until the window stops resizing, to
   // avoid overloading the control channel with notifications.
-  /** @type {remoting.ClientSession} */
-  var that = this;
-  var notifyClientDimensions = function() {
-    that.plugin.notifyClientDimensions(window.innerWidth, window.innerHeight);
-  }
-  this.notifyClientDimensionsTimer_ =
-      window.setTimeout(notifyClientDimensions, 1000);
+  this.notifyClientDimensionsTimer_ = window.setTimeout(
+      this.plugin.notifyClientDimensions.bind(this.plugin,
+                                              window.innerWidth,
+                                              window.innerHeight),
+      1000);
 
   // If bump-scrolling is enabled, adjust the plugin margins to fully utilize
   // the new window area.
@@ -727,12 +713,8 @@ remoting.ClientSession.prototype.scroll_ = function(dx, dy) {
  */
 remoting.ClientSession.prototype.enableBumpScroll_ = function(enable) {
   if (enable) {
-    /** @type {remoting.ClientSession} */
-    var that = this;
-    /** @param {Event} event */
-    this.onMouseMoveRef_ = function(event) {
-      that.onMouseMove_(event);
-    }
+    /** @type {null|function(Event):void} */
+    this.onMouseMoveRef_ = this.onMouseMove_.bind(this);
     this.plugin.element().addEventListener('mousemove', this.onMouseMoveRef_,
                                            false);
   } else {
diff --git a/remoting/webapp/connection_history.js b/remoting/webapp/connection_history.js
index cd4d5a6..da28701 100644
--- a/remoting/webapp/connection_history.js
+++ b/remoting/webapp/connection_history.js
@@ -30,14 +30,13 @@ remoting.ConnectionHistory = function() {
   /** @type {remoting.ConnectionHistory} */
   var that = this;
   var closeButton = document.getElementById('close-connection-history');
-  closeButton.addEventListener('click', function() { that.hide(); }, false);
+  closeButton.addEventListener('click', this.hide.bind(this), false);
   /** @param {Event} event Event identifying which button was clicked. */
   var setFilter = function(event) { that.setFilter_(event.target); };
-  var clearHistory = function() { that.clearHistory_(); };
   this.viewAll_.addEventListener('click', setFilter, false);
   this.viewOutgoing_.addEventListener('click', setFilter, false);
   this.viewIncoming_.addEventListener('click', setFilter, false);
-  this.clear_.addEventListener('click', clearHistory, false);
+  this.clear_.addEventListener('click', this.clearHistory_.bind(this), false);
 };
 
 /** @enum {string} */
diff --git a/remoting/webapp/host_controller.js b/remoting/webapp/host_controller.js
index 364e5c2..2236c63 100644
--- a/remoting/webapp/host_controller.js
+++ b/remoting/webapp/host_controller.js
@@ -116,7 +116,7 @@ remoting.HostController.prototype.setTooltips = function() {
 remoting.HostController.prototype.start = function(hostPin, callback) {
   /** @type {remoting.HostController} */
   var that = this;
-  var hostName = that.plugin_.getHostName();
+  var hostName = this.plugin_.getHostName();
 
   /** @return {string} */
   function generateUuid() {
@@ -242,8 +242,9 @@ remoting.HostController.prototype.stop = function(callback) {
 
   /** @param {remoting.HostController.AsyncResult} result */
   function onStopped(result) {
-    if (that.localHost && that.localHost.hostId)
+    if (that.localHost && that.localHost.hostId) {
       remoting.HostList.unregisterHostById(that.localHost.hostId);
+    }
     callback(result);
   };
   this.plugin_.stopDaemon(onStopped);
diff --git a/remoting/webapp/host_list.js b/remoting/webapp/host_list.js
index a1bb9814..d997e5b 100644
--- a/remoting/webapp/host_list.js
+++ b/remoting/webapp/host_list.js
@@ -84,12 +84,10 @@ remoting.HostList.prototype.getHostForId = function(hostId) {
  * @return {void} Nothing.
  */
 remoting.HostList.prototype.refresh = function(onDone) {
+  /** @param {XMLHttpRequest} xhr The response from the server. */
+  var parseHostListResponse = this.parseHostListResponse_.bind(this, onDone);
   /** @type {remoting.HostList} */
   var that = this;
-  /** @param {XMLHttpRequest} xhr The response from the server. */
-  var parseHostListResponse = function(xhr) {
-    that.parseHostListResponse_(xhr, onDone);
-  }
   /** @param {string?} token The OAuth2 token. */
   var getHosts = function(token) {
     if (token) {
@@ -114,12 +112,12 @@ remoting.HostList.prototype.refresh = function(onDone) {
  * include a JSON-encoded list of host descriptions, which we display if we're
  * able to successfully parse it.
  *
- * @param {XMLHttpRequest} xhr The XHR object for the host list request.
  * @param {function(boolean):void} onDone The callback passed to |refresh|.
+ * @param {XMLHttpRequest} xhr The XHR object for the host list request.
  * @return {void} Nothing.
  * @private
  */
-remoting.HostList.prototype.parseHostListResponse_ = function(xhr, onDone) {
+remoting.HostList.prototype.parseHostListResponse_ = function(onDone, xhr) {
   try {
     if (xhr.status == 200) {
       var response =
@@ -177,19 +175,6 @@ remoting.HostList.prototype.display = function(thisHostId) {
   this.errorDiv_.innerText = '';
   this.hostTableEntries_ = [];
 
-  /**
-   * @type {remoting.HostList}
-   */
-  var that = this;
-  /**
-   * @param {remoting.HostTableEntry} hostTableEntry The entry being renamed.
-   */
-  var onRename = function(hostTableEntry) { that.renameHost(hostTableEntry); }
-  /**
-   * @param {remoting.HostTableEntry} hostTableEntry The entry beign deleted.
-   */
-  var onDelete = function(hostTableEntry) { that.deleteHost_(hostTableEntry); }
-
   this.table_.hidden = (this.hosts_.length == 0);
 
   for (var i = 0; i < this.hosts_.length; ++i) {
@@ -201,7 +186,9 @@ remoting.HostList.prototype.display = function(thisHostId) {
     if (host.hostName && host.hostId && host.status && host.publicKey &&
         host.hostId != thisHostId) {
       var hostTableEntry = new remoting.HostTableEntry();
-      hostTableEntry.create(host, onRename, onDelete);
+      hostTableEntry.create(host,
+                            this.renameHost.bind(this),
+                            this.deleteHost_.bind(this));
       this.hostTableEntries_[i] = hostTableEntry;
       this.table_.appendChild(hostTableEntry.tableRow);
     }
diff --git a/remoting/webapp/host_setup_dialog.js b/remoting/webapp/host_setup_dialog.js
index 01c4947..51c713d 100644
--- a/remoting/webapp/host_setup_dialog.js
+++ b/remoting/webapp/host_setup_dialog.js
@@ -16,7 +16,6 @@ remoting.HostSetupFlow = function(sequence) {
   this.sequence_ = sequence;
   this.currentStep_ = 0;
   this.state_ = sequence[0];
-
   this.pin = '';
 };
 
diff --git a/remoting/webapp/host_table_entry.js b/remoting/webapp/host_table_entry.js
index ed1669f..ecda62f 100644
--- a/remoting/webapp/host_table_entry.js
+++ b/remoting/webapp/host_table_entry.js
@@ -181,11 +181,11 @@ remoting.HostTableEntry.prototype.updateStatus = function(opt_forEdit) {
   var clickToConnect = this.host.status == 'ONLINE' && !opt_forEdit;
   if (clickToConnect) {
     if (!this.onConnectReference_) {
-      /** @type {remoting.HostTableEntry} */
-      var that = this;
+      /** @type {string} */
+      var encodedHostId = encodeURIComponent(this.host.hostId)
       this.onConnectReference_ = function() {
         var hostUrl = chrome.extension.getURL('main.html') +
-            '?mode=me2me&hostId=' + encodeURIComponent(that.host.hostId);
+            '?mode=me2me&hostId=' + encodedHostId;
         window.location.assign(hostUrl);
       };
       this.tableRow.addEventListener('click', this.onConnectReference_, false);
@@ -225,14 +225,10 @@ remoting.HostTableEntry.prototype.beginRename_ = function() {
   this.hostNameCell_.appendChild(editBox);
   editBox.select();
 
-  /** @type {remoting.HostTableEntry} */
-  var that = this;
-  this.onBlurReference_ = function() { that.commitRename_(); };
+  this.onBlurReference_ = this.commitRename_.bind(this);
   editBox.addEventListener('blur', this.onBlurReference_, false);
 
-  /** @param {Event} event The keydown event. */
-  var onKeydown = function(event) { that.onKeydown_(event); }
-  editBox.addEventListener('keydown', onKeydown, false);
+  editBox.addEventListener('keydown', this.onKeydown_.bind(this), false);
   this.updateStatus(true);
 };
 
@@ -262,12 +258,10 @@ remoting.HostTableEntry.prototype.commitRename_ = function() {
 remoting.HostTableEntry.prototype.showDeleteConfirmation_ = function() {
   var message = document.getElementById('confirm-host-delete-message');
   l10n.localizeElement(message, this.host.hostName);
-  /** @type {remoting.HostTableEntry} */
-  var that = this;
   var confirm = document.getElementById('confirm-host-delete');
   var cancel = document.getElementById('cancel-host-delete');
-  this.onConfirmDeleteReference_ = function() { that.confirmDelete_(); };
-  this.onCancelDeleteReference_ = function() { that.cancelDelete_(); };
+  this.onConfirmDeleteReference_ = this.confirmDelete_.bind(this);
+  this.onCancelDeleteReference_ = this.cancelDelete_.bind(this);
   confirm.addEventListener('click', this.onConfirmDeleteReference_, false);
   cancel.addEventListener('click', this.onCancelDeleteReference_, false);
   remoting.setMode(remoting.AppMode.CONFIRM_HOST_DELETE);
@@ -379,10 +373,8 @@ remoting.HostTableEntry.prototype.onKeydown_ = function(event) {
  * @private
  */
 remoting.HostTableEntry.prototype.registerFocusHandlers_ = function(e) {
-  /** @type {remoting.HostTableEntry} */
-  var that = this;
-  e.addEventListener('focus', function() { that.onFocusChange_(); }, false);
-  e.addEventListener('blur', function() { that.onFocusChange_(); }, false);
+  e.addEventListener('focus', this.onFocusChange_.bind(this), false);
+  e.addEventListener('blur', this.onFocusChange_.bind(this), false);
 };
 
 /**
diff --git a/remoting/webapp/menu_button.js b/remoting/webapp/menu_button.js
index 03ad39e..ce0a2ed 100644
--- a/remoting/webapp/menu_button.js
+++ b/remoting/webapp/menu_button.js
@@ -85,7 +85,7 @@ remoting.MenuButton.select = function(item, selected) {
   } else {
     item.classList.remove('selected');
   }
-}
+};
 
 /** @const @private */
 remoting.MenuButton.BUTTON_ACTIVE_CLASS_ = 'active';
diff --git a/remoting/webapp/oauth2.js b/remoting/webapp/oauth2.js
index 6f74cbe..6024afc 100644
--- a/remoting/webapp/oauth2.js
+++ b/remoting/webapp/oauth2.js
@@ -201,10 +201,12 @@ remoting.OAuth2.prototype.clearAccessToken = function() {
  * Update state based on token response from the OAuth2 /token endpoint.
  *
  * @private
+ * @param {function(XMLHttpRequest): void} onDone Callback to invoke on
+ *     completion.
  * @param {XMLHttpRequest} xhr The XHR object for this request.
  * @return {void} Nothing.
  */
-remoting.OAuth2.prototype.processTokenResponse_ = function(xhr) {
+remoting.OAuth2.prototype.processTokenResponse_ = function(onDone, xhr) {
   if (xhr.status == 200) {
     try {
       // Don't use jsonParseSafe here unless you move the definition out of
@@ -232,6 +234,7 @@ remoting.OAuth2.prototype.processTokenResponse_ = function(xhr) {
     console.error('Failed to get tokens. Status: ' + xhr.status +
                   ' response: ' + xhr.responseText);
   }
+  onDone(xhr);
 };
 
 /**
@@ -255,15 +258,8 @@ remoting.OAuth2.prototype.refreshAccessToken = function(onDone) {
     'grant_type': 'refresh_token'
   };
 
-  /** @type {remoting.OAuth2} */
-  var that = this;
-  /** @param {XMLHttpRequest} xhr The XHR reply. */
-  var processTokenResponse = function(xhr) {
-    that.processTokenResponse_(xhr);
-    onDone(xhr);
-  };
   remoting.xhr.post(this.OAUTH2_TOKEN_ENDPOINT_,
-                    processTokenResponse,
+                    this.processTokenResponse_.bind(this, onDone),
                     parameters);
 };
 
@@ -301,16 +297,8 @@ remoting.OAuth2.prototype.exchangeCodeForToken = function(code, onDone) {
     'code': code,
     'grant_type': 'authorization_code'
   };
-
-  /** @type {remoting.OAuth2} */
-  var that = this;
-  /** @param {XMLHttpRequest} xhr The XHR reply. */
-  var processTokenResponse = function(xhr) {
-    that.processTokenResponse_(xhr);
-    onDone(xhr);
-  };
   remoting.xhr.post(this.OAUTH2_TOKEN_ENDPOINT_,
-                    processTokenResponse,
+                    this.processTokenResponse_.bind(this, onDone),
                     parameters);
 };
 
diff --git a/remoting/webapp/toolbar.js b/remoting/webapp/toolbar.js
index 0d1288e..31a5f70 100644
--- a/remoting/webapp/toolbar.js
+++ b/remoting/webapp/toolbar.js
@@ -43,13 +43,12 @@ remoting.Toolbar = function(toolbar) {
    */
   this.stubRight_ = 0;
 
-  /** @type {remoting.Toolbar} */
-  var that = this;
-
   window.addEventListener('mousemove', remoting.Toolbar.onMouseMove, false);
-  window.addEventListener('resize', function() { that.center(); }, false);
+  window.addEventListener('resize', this.center.bind(this), false);
 
   // Prevent the preview canceling if the user is interacting with the tool-bar.
+  /** @type {remoting.Toolbar} */
+  var that = this;
   var stopTimer = function() {
     if (that.timerId_) {
       window.clearTimeout(that.timerId_);
@@ -69,12 +68,10 @@ remoting.Toolbar.prototype.preview = function() {
     window.clearTimeout(this.timerId_);
     this.timerId_ = null;
   }
-  /** @type {remoting.Toolbar} */
-  var that = this;
-  var endPreview = function() {
-    that.toolbar_.classList.remove(remoting.Toolbar.VISIBLE_CLASS_);
-  };
-  this.timerId_ = window.setTimeout(endPreview, 3000);
+  var classList = this.toolbar_.classList;
+  this.timerId_ = window.setTimeout(
+      classList.remove.bind(classList, remoting.Toolbar.VISIBLE_CLASS_),
+      3000);
 };
 
 /**
diff --git a/remoting/webapp/wcs.js b/remoting/webapp/wcs.js
index 25fbbe0..4906c82 100644
--- a/remoting/webapp/wcs.js
+++ b/remoting/webapp/wcs.js
@@ -52,26 +52,15 @@ remoting.Wcs = function(wcsIqClient, token, onReady) {
    */
   this.clientFullJid_ = '';
 
-  /** @type {remoting.Wcs} */
-  var that = this;
+  var updateAccessToken = this.updateAccessToken_.bind(this);
+
   /**
    * A timer that polls for an updated access token.
    * @type {number}
    * @private
    */
   this.pollForUpdatedToken_ = setInterval(
-      function() {
-        /** @param {string?} token */
-        var updateAccessToken = function(token) {
-          if (token) {
-            that.updateAccessToken_(token);
-          } else {
-            console.error('pollForUpdatedToken: Authentication failed.');
-            // No need to update the token. The hanging GET will fail anyway.
-          }
-        }
-        remoting.oauth2.callWithToken(updateAccessToken);
-      },
+      function() { remoting.oauth2.callWithToken(updateAccessToken); },
       60 * 1000);
 
   /**
@@ -82,9 +71,7 @@ remoting.Wcs = function(wcsIqClient, token, onReady) {
   this.onIq_ = function(stanza) {};
 
   // Handle messages from the WcsIqClient.
-  /** @param {Array.<string>} msg An array of message strings. */
-  var onMessage = function(msg) { that.onMessage_(msg); };
-  this.wcsIqClient_.setOnMessage(onMessage);
+  this.wcsIqClient_.setOnMessage(this.onMessage_.bind(this));
 
   // Start the WcsIqClient.
   this.wcsIqClient_.connectChannel();
@@ -98,7 +85,10 @@ remoting.Wcs = function(wcsIqClient, token, onReady) {
  * @private
  */
 remoting.Wcs.prototype.updateAccessToken_ = function(tokenNew) {
-  if (tokenNew != this.token_) {
+  if (!tokenNew) {
+    console.error('updateAccessToken_: Authentication failed.');
+    // No need to update the token. The hanging GET will fail anyway.
+  } else if (tokenNew != this.token_) {
     this.token_ = tokenNew;
     this.wcsIqClient_.updateAccessToken(this.token_);
   }