commit 1fbd25336aad5c108012a4a5a415c18c3ce06e86
author Cosmos Nicolaou <cnicolaou@google.com> Sun Dec 06 10:43:25 2015 -0800
committer Cosmos Nicolaou <cnicolaou@google.com> Sun Dec 06 19:07:59 2015 +0000
tree 203bd3d1addceb8223e10c5139d7cf379e02d2b0
parent 1a108dff212c15b6f0f8b4e797cd318f6da0b48e

TBR: v.io/jiri: fix a race condition in runtile/sequence.go

Share a lock across all writers passed to Capture regardless
of if they are the same or not. This handles cases of the form

var out bytes.Buffer
stdout := io.MultiWriter(&out, jirix.Stdout())
stderr := io.MultiWriter(&out, jirix.Stdout())
s.Capture(stdout, stderr).Run....

where the same underlying output stream is aliased via
a wrapper.

Change-Id: Idbe010b14de992a30c35793e6c562ce26f3406a8