Optimizing: Avoid unnecessary work in `LinearScan()`. am: aa42bf962c

Original change: https://android-review.googlesource.com/c/platform/art/+/3553643

Change-Id: I44c1a40e1f840d5ab908135fdcae7332bb032211
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>