Dump warning logs to prevent app crash while no top-resumed changes

Applications crashed due to duplicated top resumed activity change
events. Currently, the only possible scenario we know if that the
application invokes Looper#loop() and reverse the messages order.

Write warning logs vs. throwing exceptions to prevent application
crashes.

Bug: 140571893
Test: build and boot pass
Change-Id: If6f6c502b96ccc11b230ba075c61118f03e13d5c