[automerger skipped] Check for system_other existence in recovery mode as well. am: ddf27738af -s ours am: 3ae912f9fe -s ours am: 509ec47495 -s ours

am skip reason: Change-Id I1884755aad2a8d37f540dbee73c7c7baab2759e7 with SHA-1 ddf27738af is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/update_engine/+/11796618

Change-Id: I291b1e4ec8f829d17e6297ed117783fedcda83b4