[automerger skipped] binder: fix FD handling in continueWrite am: aff1772 -s ours

am skip reason: Merged-In Iadf7e2e98e3eb97c56ec2fed2b49d1e6492af9a3 with SHA-1 c0ad6b0 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/native/+/29883763

Change-Id: Ia260b1ce472f7ec784d5c509353bc5b11b72ff6e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

Author: fkm3