Move compiled methods to use AtomicMethodRefMap

Use AtomicMethodRefMap to avoid locking and map costs.

Native RAM usage for interpret-only compile FB:
71270192B -> 64117168B

Perf:
CompilerDriver::GetCompiledMethod: 0.88% -> 0.04%
Mutex::ExclusiveLock: 1.55% -> 1.05%

Bug: 32641252

Test: test-art-host-run-test

Change-Id: I146e7bf2f3328b4fa84f2cc19d591f4da82dccfc
4 files changed