Merge "Lock down String8.isEmpty() usage" into main am: 358a982b71 am: b19c86cdd3 am: 1263ea0299 am: 457c96513d

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2705824

Change-Id: I72d999f96098a10dce2037a43de7fb6ea7ec7811
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>