Add Application.Delegate.stop.

remoting/webapp/app_remoting/js/app_remoting.js

Index: remoting/webapp/app_remoting/js/app_remoting.js
diff --git a/remoting/webapp/app_remoting/js/app_remoting.js b/remoting/webapp/app_remoting/js/app_remoting.js
index fb14f6d06827f24e5a6490fff0a577a5fba0002d..d5cdd94dddd1146be06dc8826015a5e3e29f2f3c 100644
--- a/remoting/webapp/app_remoting/js/app_remoting.js
+++ b/remoting/webapp/app_remoting/js/app_remoting.js
@@ -184,12 +184,14 @@ remoting.AppRemoting.prototype.start = function(connector, token) {
  * @param {remoting.Error} error The failure reason.
  */
 remoting.AppRemoting.prototype.signInFailed = function(error) {
-  if (error == remoting.Error.CANCELLED) {
-    chrome.app.window.current().close();
-    remoting.LoadingWindow.close();
-  } else {
-    this.handleError(error);
-  }
+  this.handleError(error);
+};
+
+/**
+ * Close the loading window before exiting.
+ */
+remoting.AppRemoting.prototype.stop = function() {
+  remoting.LoadingWindow.close();
 };
 
 /**