[PATCH 2 of 4 V3] chg: implement validate in hgclient

[Yuya Nishihara]

On Sat, 5 Mar 2016 14:00:11 +0000, Jun Wu wrote:
> # HG changeset patch
> # User Jun Wu <quark at fb.com>
> # Date 1457185617 0
> #      Sat Mar 05 13:46:57 2016 +0000
> # Node ID cb345048855bb8e47ca28a13388fb3291e7aee2e
> # Parent  f9ac561d5843234187751a508b6d557e8903ceac
> chg: implement validate in hgclient

It seems the list is somehow lagging. I received the V5 via IRC and pushed
it to the clowncopter, many thanks.

> +	writeblockrequest(hgc, "validate");
> +	readchannel(hgc);

s/readchannel/handleresponse/ to make sure data was written to 'r' channel.