Wake screen from external HID peripherals.

Added some plumbing to enable the policy to intercept motion
events when the screen is off to handle wakeup if needed.

Added a basic concept of an external device to limit the scope
of the wakeup policy to external devices only.  The wakeup policy
for internal devices should be based on explicit rules such as
policy flags in key layout files.

Moved isTouchEvent to native.

Ensure the dispatcher sends the right event type to userActivity
for non-touch pointer events like HOVER_MOVE and SCROLL.

Bug: 3193114
Change-Id: I15dbd48a16810dfaf226ff7ad117d46908ca4f86