ART: Refactor CommonRuntimeTest::SetUp

Factor out finishing up the runtime. This code will execute the
interpreter to initialize important classes etc., which is not
necessary for testing RuntimeMethod sizes and trampoline entrypoints,
in fact it may violate pointer-size invariants.

Also add InstructionSet parsing tests to the ParsedOptions test.

Change-Id: I75cd00c6d358e1bc962c8f1845244f6400c1cd6c