[automerger skipped] Merge Android R (rvc-dev-plus-aosp-without-vendor@6692709) am: 7088c5a113 -s ours am: e91bce09e8 -s ours am: 7b57d7e31a -s ours

am skip reason: Change-Id I716019210e2540744f308510fed6ad0483c14e62 with SHA-1 17e308f8a6 is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/libbackup/+/12470072

Change-Id: I1afe78b59239dfdcf4f728a249ab074bd6214bd4