Use virtual dispatch for `MethodHandle.asType()`.

The non-virtual dispatch was a mistake in
    https://android-review.googlesource.com/1944906 .

Change well known method handle methods to `ArtMethod*`.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Test: atest CtsLibcoreTestCases
Change-Id: I3670ca6a229942e2edbd351a922f83f5d20d0c09
5 files changed