[PATCH] histedit: use the unfiltered repository to get rulectx

[Jun Wu]

I like this change and the code looks good to me.

Excerpts from timeless's message of 2016-06-03 14:54:14 +0000:
> # HG changeset patch
> # User timeless <timeless at mozdev.org>
> # Date 1464965033 0
> #      Fri Jun 03 14:43:53 2016 +0000
> # Node ID bdcf6e2abe8ff449de33fb58d2488f7f60564e22
> # Parent  9ac309946df9e69bb73ded75f2fc5b84a4e785c2
> # Available At https://bitbucket.org/timeless/mercurial-crew 
> #              hg pull https://bitbucket.org/timeless/mercurial-crew  -r bdcf6e2abe8f
> histedit: use the unfiltered repository to get rulectx
> 
> Without this, histedit fails if a node was pruned.
> But histedit just wants the commit info, it does not need to care if
> a node is dead or alive.