Revert "Revert "CHA for abstract methods.""

This reverts commit 8ebc8bf055e8bd8f6f167e65a69cf4dae136db55.

When we set the single-implementation method for an abstract method, it
need to be protected by the cha-lock.

Test: new testcase and ART_TEST_JIT=true m -j20 test-art-host-run-test
Change-Id: I66acb20ffa7e49dd9c391f001e3bb52f961872e4
10 files changed