Implement JVMTI GetCurrentContendedMonitor

Adds the JVMTI can_get_current_contended_monitor capability and
implements all associated functions and behaviors.

Test: ./test.py --host -j50
Bug: 62821960
Bug: 34415266
Change-Id: Ia3f19f0fbb21125bc85fb71f55e52ec61141c4ec
19 files changed