Merge "Remove exception for injecting pointer event from sendTrackballEventSync" into tm-dev

     */

    public void sendTrackballEventSync(MotionEvent event) {

        validateNotAppThread();

        if (event.isFromSource(InputDevice.SOURCE_CLASS_POINTER)) {

            throw new IllegalArgumentException(

                    "Cannot inject pointer events from sendTrackballEventSync()."

                            + " Use sendPointerSync() to inject pointer events.");

        }

        if (!event.isFromSource(InputDevice.SOURCE_CLASS_TRACKBALL)) {

            event.setSource(InputDevice.SOURCE_TRACKBALL);

        }