Add presubmit trybot for skia.

masters/master.client.skia.fyi/builders.cfg

Index: masters/master.client.skia.fyi/builders.cfg
diff --git a/masters/master.client.skia.fyi/builders.cfg b/masters/master.client.skia.fyi/builders.cfg
index 469e21905e22ca8c2a513dc3e10f5bae69e87c82..1fa851b2864523f8b2af60550b92d3a0efedbe14 100644
--- a/masters/master.client.skia.fyi/builders.cfg
+++ b/masters/master.client.skia.fyi/builders.cfg
@@ -16,4 +16,10 @@ builders = [
   { 'name': 'Infra-PerCommit',
     'recipe': 'skia/infra',
     'scheduler': 'infra_percommit' },
+  { 'name': 'skia_presubmit',
+    'recipe': 'run_presubmit',
+    'properties': {
+      'repo_name': 'skia',
+    },
+    'do_trybot': True },

[borenet, 2015/05/12 16:33:50]

Just so you're aware, this will create two bots:
- skia_presubmit
- skia_presubmit-Trybot

That's fine with me - there's value in having a waterfall bot running the
presubmit.

[Adrian Kuegel, 2015/05/18 11:44:26]

I was not actually aware of this, I only wanted to create the
skia_presubmit-Trybot. But you are right, there is also value in having a
waterfall bot. And it looks to me like skia_master_utils.py does not allow to
create just a Trybot without the waterfall bot as well.

[borenet, 2015/05/18 12:05:49]

Yeah, the skia_master_utils were created under the assumption that we almost
always want to duplicate our waterfall bots as trybots.  I don't know that we've
ever needed to add a trybot that wasn't a clone of one of our waterfall bots.

 ]