Set ActivityView's rect as tap exclude region

Track bounds of an ActivityView and set them as a tap exclude region,
so that taps on this area won't cause a focus switch between
hosting activity and activities inside of ActivityView.

Bug: 63902362
Test: Manual with ActivityView test app
Change-Id: I3cdafe32e0bdf414507fef0d622d9c140eee3188
8 files changed