Switch-interpreter: Add boolean return value to opcodes.

Currently unused - this is in preparation for future CLs.

The intention is that "return false" must always immediately
propagate all the way to the main loop, which can then use
it to handle abnormal cases in uniform and localized way.

Test: ./art/test.py -b --host --64 --interpreter
Change-Id: I21b0a26b08488add0af4825469f68c6cbf507106
1 file changed