Revert "Revert "Revert "Revert "Correct nullability and final constraints on new APIs.""""

This reverts commit 2fac9dd3d4d58229ff9edad75b00a28befb2ffc2.

Reason for revert: the change being reverted was not supposed to be
merged into git_master.

Change-Id: Ieb9169fdd242edb72774e5c3d5824bc54b55cc05
4 files changed