Fix class_def_idx increment for FastVerify

Fixes vdex golem benchmarks.

Also fixed logic that was overwriting the expected ClassStatus for
debug builds. This is why the tests were passing but the CHECK was
failing for non debug dex2oat.

Added regression test in dex2oat_test.

Bug: 80309967
Test: test-art-host
Change-Id: I91c48ffbe894ab471572418142fcb4ae85bf0864