[base] Change Dirname/Basename params to string_view am: 2902e107c0

Original change: https://android-review.googlesource.com/c/platform/system/libbase/+/2322235

Change-Id: I5213fb5406cbcf26eeb4a76b71d9d1ad8ba3dce0
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>