Fixed ISE issue when subscribing to gcm groups from the main thread.

    @Override

    protected void onStop() {

        super.onStop();

        AlertService.updateAlertNotification(this);

        // Can't run updateAlertNotification in main thread

        AsyncTask task = new AsyncTask<Context, Void, Void>() {

            @Override

            protected Void doInBackground(Context ... params) {

                AlertService.updateAlertNotification(params[0]);

                return null;

            }

        }.execute(this);

        if (mCursor != null) {

            mCursor.deactivate();