syncInputWindows for mouse events

Add back the syncInputWindows calls for mouse events, because there are
tests that rely on this behaviour (they might inject only a few events,
which is not very realistic, but we still have to support this).

Bug: 137072767
Bug: 138263890
Test: atest android.view.cts.HoverTest
Change-Id: I37b621bc6dc6a844ca86324962124bb06857b906