message: Fix protocol handler unit test
diff: @@ -1989,7 +1989,8 @@ TEST_F(ProtocolHandlerImplTest, SendHeartBeat_Successful) {
  transport_manager_mock,
  SendMessageToDevice(ExpectedMessage(
  FRAME_TYPE_CONTROL, FRAME_DATA_HEART_BEAT, PROTECTION_OFF, kControl)))
  - .WillOnce(Return(E_SUCCESS));
  + .WillOnce(DoAll(NotifyTestAsyncWaiter(waiter), Return(E_SUCCESS)));
  + times++;
  // Act
  protocol_handler_impl->SendHeartBeat(connection_id, session_id);
  @@ -2086,7 +2087,8 @@ TEST_F(ProtocolHandlerImplTest,
  transport_manager_mock,
  SendMessageToDevice(ExpectedMessage(
  FRAME_TYPE_SINGLE, FRAME_DATA_SINGLE, PROTECTION_OFF, kControl)))
  - .WillOnce(Return(E_SUCCESS));
  + .WillOnce(DoAll(NotifyTestAsyncWaiter(waiter), Return(E_SUCCESS)));
  + times++;
  // Act
  protocol_handler_impl->SendMessageToMobileApp(message, is_final);
  