Merge "Revert "Revert "Drop all path-related methods from android::String8""" into main am: b2b037d9f0 am: e4fc1fb947 am: 4b17b30ab8 am: 398b95b5ab

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2745823

Change-Id: I4b48343911ebc7d9d4d2a676fadd612c57d4d67c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>