Speed up GraphChecker::VisitInstruction am: 8533e7b40d

Original change: https://android-review.googlesource.com/c/platform/art/+/2935181

Change-Id: Id1bec6e2f398040d85f172e254222e5cadcb4d55
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>