Replace string copies with const-ref am: 121fedaa46 am: e331953c90

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2869314

Change-Id: Id2c0b42c43cedcc48368cd266a696cfdc31d8ade
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>