Add linux_clang to default try set

Add linux_clang to default try set so when one runs `git try` or `gcl try` it
will add linux_clang automatically.

TEST=Less tree breakage because of not trying changes on clang first.
BUG=None
NOTRY=true

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=122041

[Dan Beam, 2012-02-14 23:43:46]

Tell me if there's somebody else I should be giving this to.

[M-A Ruel, 2012-02-14 23:45:17]

https://chromiumcodereview.appspot.com/9395027/diff/2001/PRESUBMIT.py
File PRESUBMIT.py (right):

https://chromiumcodereview.appspot.com/9395027/diff/2001/PRESUBMIT.py#newcode337
PRESUBMIT.py:337: affected_files = [f.LocalPath() for f in
change.AffectedFiles()]
You want change.LocalPaths()

[Dan Beam, 2012-02-14 23:50:28]

https://chromiumcodereview.appspot.com/9395027/diff/2001/PRESUBMIT.py
File PRESUBMIT.py (right):

https://chromiumcodereview.appspot.com/9395027/diff/2001/PRESUBMIT.py#newcode337
PRESUBMIT.py:337: affected_files = [f.LocalPath() for f in
change.AffectedFiles()]
On 2012/02/14 23:45:17, Marc-Antoine Ruel wrote:
> You want change.LocalPaths()

Done.

[M-A Ruel, 2012-02-15 00:00:58]

lgtm

[commit-bot: I haz the power, 2012-02-15 02:47:45]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/dbeam@chromium.org/9395027/2002

[commit-bot: I haz the power, 2012-02-15 04:21:37]

Change committed as 122041