Revert "Revert "More flexible API enforcement policy.""

This reverts commit 1bc41d4c7d3622dd4b42ed49c804a7e97fdaf2f5.

Reason for revert: Re-submitting after fixing tests.

Test: See original change
Change-Id: Idd73c9938592c5c4d67cfb9efefdffed0dd5f262
4 files changed