Merge "replace char * with std::string" into rvc-dev am: 56c303b7 am: 22adeeaf am: 368d21e9

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/11687549

Change-Id: I35878bcd92f82a030843f76639318c349f52eb58