Simplify DexRegisterMap API.

Store some of the needed decoding state explicitly to avoid passing it
around all the time. The DexRegisterMap class is rewritten in next CL.

Test: test-art-host-gtest-stack_map_test
Change-Id: Ie268dff2a1c1da2e08f0e6799ae51c30e11f350b
11 files changed