ART: Faster VarHandle accessors for exact callsite matches

Adds a faster path for VarHandle accessors invoked through the
runtime. The code previously assumed that some kind of argument or
return type conversion would be necessary.

Bug: 73275005
Test: art/test.py --host --gcstress -r -t 712
Change-Id: Ie27c6d8c3bdf80f5932d38d19c67a6bf633af8f0
4 files changed