Merge "libshmem: don't depend on unique_fd cast to int" into main am: 0161347a

Original change: https://android-review.googlesource.com/c/platform/frameworks/av/+/2834954



Change-Id: I261a636a1d4f3fcf0c6e59b702cbf2e0bc478693
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>