[automerger skipped] storageproxy: Report fsync failures with a distinct error...

[automerger skipped] storageproxy: Report fsync failures with a distinct error code am: cf458bae -s ours am: 1c8475e6 -s ours

am skip reason: Merged-In Ie9d4a1949586e90006256c975786e21ced655e66 with SHA-1 1c75d1e3 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/19517837



Change-Id: Ia778a4c0b9f5d58b71c7bb2801d0c20ecf5f656c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>