CL 388915 added an exported API but was authored (and tested)
before the API check became stricter.
Updates #46057.
Change-Id: Iee6e4969ade77fb0539fa97fcef0047389fb2cf6
Reviewed-on: https://go-review.googlesource.com/c/go/+/398237
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>