We also need to delete osr entries when deleting ArtMethod.

We also need to delete osr entries when deleting ArtMethod.

In the unfortunate event an ArtMethod gets allocated at the
same location as an old (deleted) ArtMethod, the osr_code_map_
lookup will succeed and return garbage. So we need to delete
entries in the osr_code_map_ when an ArtMethod gets deleted.

This should finally fix:
dalvik.system.DexClassLoaderTest#test_twoJar_diff_getResourceAsStream

Change-Id: I7c8b775c3376a6cfcb907f09b783e393967ad82d