Pilfer pointers if touchable area isn't overlay with focus window

Otherwise, the motion event can be send to the app at that point,
then the non-focusd app can process that touch event.

Bug: 343911297
Bug: 343910450
Test: Tried with app has letterbox and the app using activity embedded.
The gesture motion event shouldn't dispatch to non-focused window.

Change-Id: I7bd52c3e34a501b0dbc5a58e601982f795267d49