CHA for abstract methods.

Add the ability to devirtualize abstract method invocation if
an abstract method has only one implementation. Only support in JIT
mode currently.

Test: new testcase and ART_TEST_JIT=true m -j20 test-art-host-run-test
Change-Id: I43da03a9fa9a73840f5eaf207c6611e0913a7f66
10 files changed