Allow injected events to specify repeatCount

Injected key events may contain repeatCount. Currently, all injected
events are hardcoded to have zero key repeat. This breaks any injected
key event that simulates long-press behaviour.

To fix this, ensure that we are using the specified repeatCount from the
injected event.

Test: atest KeyEventInjectionTest
Bug: 113341746
Change-Id: Ic663df984703b04f021e428463868293366b4250