[PATCH 2 of 2] strip: make tree stripping O(changes) instead of O(repo)

[Augie Fackler]

On Mon, May 08, 2017 at 11:40:03AM -0700, Durham Goode wrote:
> # HG changeset patch
> # User Durham Goode <durham at fb.com>
> # Date 1494268523 25200
> #      Mon May 08 11:35:23 2017 -0700
> # Node ID 74881b9a39b2bab273d09009385e3c9ca717a13a
> # Parent  5dec5907fe49a488d3ade272d4a5cf090914e59c
> strip: make tree stripping O(changes) instead of O(repo)

queued, thanks