make MotionEventInjector support multi-display

Although we have MotionEventInjector for each display but it always
inject events to default display. We set display id of the motion events
to make it correct.

Test: atest MotionEventInjectorTest
Test: atest AccessibilityGestureDetectorTest
Test: atest AccessibilityServiceConnectionTest
Bug: 138422679
Change-Id: I8cfbe9887109e001ea64ca0c250606684be370e7