title: GCM after un-register still receive notification
body: <p>I wanted to un-register GCM after user clicked on a button. I tried the following codes for un-register but still even after all these initialized I still managed to push notification to the device. Please let me know if I'm missing anything here.</p>
  
  <pre><code>@Override
  public boolean onOptionsItemSelected(MenuItem item) {
      switch(item.getItemId()) {
          case R.id.options_logout:
              ServerUtilities.unregister(getApplicationContext(), ServerUtilities.registrationID);
              unRegisterGCM();
              return true;
          case R.id.options_exit:
              finish();
              return true;
          default:
              return super.onOptionsItemSelected(item);
      }
  }
  
  @Override
  protected void onDestroy() {
      Log.i(TAG,"onDestroy.........");
      helper.close();
      if (mRegisterTask != null) {
          mRegisterTask.cancel(true);
      }
      unregisterReceiver(mHandleMessageReceiver);
      super.onDestroy();
  }
  
  public void unRegisterGCM(){
      Intent unregIntent = new Intent("com.google.android.c2dm.intent.UNREGISTER");
      unregIntent.putExtra("app", PendingIntent.getBroadcast(this, 0, new Intent(), 0));
      startService(unregIntent);
  
      Intent intent = new Intent(MessageList.this, LoginScreen.class);
      intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
      startActivity(intent);
      finish();
  }
  </code></pre>
  
  <p><strong>Log</strong></p>
  
  <pre><code>04-12 16:20:23.039: I/MessageList(1912): onDestroy.........
  04-12 16:20:26.523: V/GCMBroadcastReceiver(1912): onReceive: com.google.android.c2dm.intent.REGISTRATION
  04-12 16:20:26.523: V/GCMBroadcastReceiver(1912): GCM IntentService class: com.mon.GCMIntentService
  04-12 16:20:26.523: V/GCMBaseIntentService(1912): Acquiring wakelock
  04-12 16:20:26.531: V/GCMBaseIntentService(1912): Intent service name: GCMIntentService-0987654321-2
  04-12 16:20:26.531: E/GCMRegistrar(1912): internal error: retry receiver class not set yet
  04-12 16:20:26.531: V/GCMRegistrar(1912): Registering receiver
  04-12 16:20:26.535: D/GCMBaseIntentService(1912): handleRegistration: registrationId = null, error = null, unregistered = com.mon
  04-12 16:20:26.535: D/GCMRegistrar(1912): resetting backoff for com.fl.monitor
  04-12 16:20:26.535: V/GCMRegistrar(1912): Saving regId on app version 1
  04-12 16:20:26.621: I/GCMIntentService(1912): Device unregistered
  04-12 16:20:26.621: V/GCMRegistrar(1912): Is registered on server: false
  04-12 16:20:26.621: I/GCMIntentService(1912): Ignoring unregister callback
  04-12 16:20:26.621: V/GCMBaseIntentService(1912): Releasing wakelock
  04-12 16:20:58.156: V/GCMBroadcastReceiver(1912): onReceive: com.google.android.c2dm.intent.RECEIVE
  04-12 16:20:58.156: V/GCMBroadcastReceiver(1912): GCM IntentService class: com.mon.GCMIntentService
  04-12 16:20:58.156: V/GCMBaseIntentService(1912): Acquiring wakelock
  04-12 16:20:58.160: V/GCMBaseIntentService(1912): Intent service name: GCMIntentService-1234567890-3
  04-12 16:20:58.164: I/GCMIntentService(1912): Received message
  04-12 16:20:58.167: I/GCMIntentService(1912): project:GHI
  </code></pre>