Modify pilferpointers API to selectively cancel pointers

Behavior changes:
- Pilfer pointers only cancels relevant pointers (If a pointer
is used by the window calling pilferPointers(), only then,
we need to send ACTION_CANCEL/POINTER_UP to other windows using
that particular pointer)
- Any pointers not used by the window calling pilferPointers()
will remain unaffected and the windows using them will keep
receiving the events
- Any future Pointer down events will go to other windows if and
only if the "the pilfering window" that called pilferPointers() do
not need that pointer for its gesture detection (the pointer down
occurs outside the touchable bounds of the pilfering window)

Bug: 220109830
Test: atest inputflinger_tests

Change-Id: Idc59ae06352560fefd7274bc043bd6e72d5e7710