wm: Simplify menu action decision paths

Since the action is performed directly from the handler, remove all
fallback paths and "if not default action" checks; these are superfluous,
and can send the wrong events to apps implementing their own input handlers.

Change-Id: Iaafe9c7a1ab0ab75ae93f1c8a6e1efb6c7a616cb
Merge "wm: Simplify menu action decision paths" into cm-11.0