Merge "minor doc improvement for tombstone fd code" into main am: 1076e7f7 am: a1e77283

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2976171



Change-Id: Ie328b54471ff77b6d181f91cb029cee0c5e9255a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>