Automatic merge from submit-queue (batch tested with PRs 39673, 39536, 39617, 39540, 39686)

remove API to server library dependency

A client library (which must include api types), should not depend on our server library.  This duplicates one constant for conversion to avoid the link.

@smarterclayton @liggitt

The import-boss rule to keep us from forming these dependencies is non-trivial since some of the bits under /apis are server only (validation for instance).