Revert "Rename Flush to Finalize"

This reverts commit 6177f6f6.

Reason for revert: Droidcop-triggered revert due to breakage https://android-build.googleplex.com/builds/quarterdeck?branch=aosp-master&target=sdk_x86-sdk&lkgb=6919873&lkbb=6919923&fkbb=6919923, bug b/171353958

Change-Id: Iea3059b4bf64a7cac930c40b8b312b5b26b0baea
BUG: 168829493