Refactor PWM to fully capture shortcut gesture

Currently some keys and shortcuts are partially captured. So,
a part of the key event gesture is sent to applications and a part
of it is not.
Make sure keys and shortcuts are tracked from first action down, and
if they are intercepted the whole key event gesture, down, repeated
down, up are all intercepted.
Example: In the current logic some keys were getting captured only
on first ACTION_DOWN, this means applications were still receiving
ACTION_UP which they should not since they didn't receive the down
event.

Further refactoring: Fix interceptBeforeQueuing and separate the logic
to a separate file to handle shortcuts and add more strict testing.

Test: manual
Bug: 283241997
Change-Id: Ia48086458c86b35c00e01b4a960f6a9bfb80bae9