Add config for Linux layout test try bot with --enable-slimming-paint-v2.

masters/master.tryserver.chromium.linux/master.cfg

Index: masters/master.tryserver.chromium.linux/master.cfg
diff --git a/masters/master.tryserver.chromium.linux/master.cfg b/masters/master.tryserver.chromium.linux/master.cfg
index f5213bf9e0f1ba5b920d6ce045d6c4082c8129f0..9edb315e7ec9e1b51ec042b3414c855f6fbce0ab 100644
--- a/masters/master.tryserver.chromium.linux/master.cfg
+++ b/masters/master.tryserver.chromium.linux/master.cfg
@@ -275,6 +275,12 @@ chromium_builders.append({
   'slavebuilddir': 'linux',
 })
 
+# Builder specifically to run layout tests with a particular flag (see crbug.com/622865).
+chromium_builders.append({
+  'name': 'linux_layout_tests_slimming_paint_v2',
+  'factory': baseFactory('chromium_trybot'),

[Paweł Hajdan Jr., 2016/07/22 13:36:12]

Please use m_remote_run instead of baseFactory.

[qyearsley, 2016/07/22 16:42:06]

Done.

+})
+
 # Presubmit bots
 def presubmit(name, slavebuilddir=None, extra_props=None):
   properties = {'repo_name': name}