ART: Disambiguate access-checks mode from lock-counting

Lock-counting (when structural locking verification failed) is a
special sub-mode of access-checks and must be disambiguated, because
we currently use access-checks mode class-wide when at least one
method soft-fails, but do not stop the compiler/JIT to compile
the "working" methods. So we may end up in the access-checks
interpreter for a working method through deopt without knowing
which locks are already held.

Bug: 28351535
Change-Id: I083032f064d88df8f8f0611ad8b57d1b39cd09fb