Revert "Revert "Make JVMTI DisposeEnvironment and GetEnv thread safe.""

This reverts commit af934108.

We needed to allow TopLockLevel locks to be acquired when the
mutator_lock_ is exclusive held. This is required for spec
conformance. To ensure there are no deadlocks the mutator_lock_ is the
only lock level with this exception and one cannot acquire the
mutator_lock_ when one holds any kTopLockLevel locks.

Reason for revert: Fixed issue causing test 913 failure in art-gc-gss-tlab
Test: ART_DEFAULT_GC_TYPE=GSS \
      ART_USE_TLAB=true \
      ART_USE_READ_BARRIER=false
      ./test.py --host -j50
Bug: 69465262

Change-Id: Ic1a4d9bb3ff64382ba7ae22ba27a4f44628ed095