Catching additional case where menu would disappear in accessibility.

- When showing the menu via accessibility it will stay on screen until
  the user focuses away, but exploring via talkback still sends
  onUserInteraction() callbacks which would post it anew.  We need to
  save the timeout state whenever the menu is shown and check it there
  as well.

Bug: 36103023
Test: Enter PIP with talk back, touch button but don't do anything for
      the timeout (~4s), verify menu does not close.

Change-Id: I03ce14531fcde84440122bfb0fc70899f5178d5b