Fixing bug when model was not reflected properly on the UI.

If launcher submits a job, and then reloads before the job is executed, the correct model
is not reflected on the Launcher. In that case, we simply rebind the launcher

Change-Id: I380242a4de13e7b2bc326d1a076f0a974435999c

src/com/android/launcher3/model/BgDataModel.java

@@ -105,6 +105,11 @@ public class BgDataModel {
      */
     public final WidgetsModel widgetsModel = new WidgetsModel();
 
+    /**
+     * Id when the model was last bound
+     */
+    public int lastBindId = 0;
+
     /**
      * Clears all the data
      */