Merge "fs_mgr_overlayfs: Remove backing image if failed to allocate scratch" am: 25eb51a9

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2273047



Change-Id: I7def2feb85f2f2c284564a68332a7a5c39f556d2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>