Replace chrome string util with android base ones am: b9a9aa22ba

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/3309177

Change-Id: Id29d8800aa422649a605cc45322154ea6e15bff5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>