Handle methods being present in multiple threads correctly

We were incorrectly removing obsolete methods from the jit too early.
This could cause stack walking to fail on other threads that also have
the same method present. This changes so we will not notify the jit of
obsoleted methods until we have walked all threads.

Test: ./test.py --host
Bug: 73333076
Change-Id: I30b1293eaf2dac7d4af858f77e5819af2d96b429
16 files changed