Fix potential synchronized race between SF and InputFlinger

The 'CountDownLatch' is used to control the synchronization behavior if
a transaction is synchronous or contains the syncInputWindow command,
while updating input windows asynchronously, if there is another
synchronized transaction queued and commited before input windows
updated, it may cause the transaction return early and cause other input
function such as 'transferTouchFocus' failed.

This CL distinguish the transaction and input windows updating
synchronization that could help to signal the CountDownLatch in correct
situation.

Test: atest SurfaceFlinger_tests
Test: atest CrossDragAndDropTests --rerun-until-failure 50
Bug: 183877670
Bug: 183877512
Bug: 183880412
Change-Id: I68e124006e86d8b9c4b8c528418b9db2065b21de