[AppRemoting] Implement ConnectionDroppedDialog.

remoting/webapp/app_remoting/js/app_connected_view.js

Index: remoting/webapp/app_remoting/js/app_connected_view.js
diff --git a/remoting/webapp/app_remoting/js/app_connected_view.js b/remoting/webapp/app_remoting/js/app_connected_view.js
index 693385a4071a24a7beaca90aaa7286a6ededc75c..5ed85ed3b0c4365f6e47fb7da5e451adfa7d4c92 100644
--- a/remoting/webapp/app_remoting/js/app_connected_view.js
+++ b/remoting/webapp/app_remoting/js/app_connected_view.js
@@ -74,8 +74,9 @@ remoting.AppConnectedView = function(containerElement, connectionInfo) {
       this.onDesktopSizeChanged_.bind(this));
 
   /** @private */
-  this.disposables_ = new base.Disposables(
-      baseView, windowShapeHook, desktopSizeHook, this.contextMenu_);
+  this.disposables_ =
+      new base.Disposables(baseView, windowShapeHook, desktopSizeHook,
+                           this.contextMenu_, menuAdapter);

[Jamie, 2015/05/20 02:20:36]

Is this change related to this CL?

[kelvinp, 2015/05/20 18:12:59]

Because, this change allow us to restart the AppRemotingActivity., each
component must be able to shutdown cleanly.  We add the menuAdaptor to the list
of disposables so that it can clean up its context menu, or else ChromeOS will
complain double registration of the same menu item. 

 
   /** @private */
   this.supportsGoogleDrive_ = this.plugin_.hasCapability(