This allows us to hook functionality from the main tools repository with
alternate or extended implementations.
Change-Id: Ibc66cdd15ee80f1104a8464f1e28763a41d5765a
Reviewed-on: https://go-review.googlesource.com/c/tools/+/196319
Run-TryBot: Ian Cottrell <iancottrell@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
