Introduce FindSuperMethodToCall to find the target of a super call.

And use it across compiler/runtime/nterp. This also fixes an issue in
nterp when handling an obsolete method.

Also move FindMethodFast and FindFieldFast next to their only use.

Test: test.py
Bug: 214328881
Change-Id: If64849575ae342324e30026e29d285eca6e61263
8 files changed