Use framework-supplied keycode symbols.

KeyEvent now offers an (@hidden) method to map keycodes to symbolic names
in a way that is compatible with what Monkey was already doing itself.
Now we shouldn't need to change monkey each time we add new keycodes.

Bug: 2912307
Change-Id: I9cd729b17c3f19505a4d3afcce465dad0c64cce0
2 files changed