Merge "Reduce locking during IO heavy operations." into udc-dev am: c595199741 am: 39e13f030d am: 0ce16784a7 am: 0de504d7c6

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22806609

Change-Id: I870de41b270cc11b576f7267a5ebdfd0bc1042b7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>