Adding Findit variable builders corresponding to those in chromium.webkit

masters/master.tryserver.chromium.mac/slaves.cfg

Index: masters/master.tryserver.chromium.mac/slaves.cfg
diff --git a/masters/master.tryserver.chromium.mac/slaves.cfg b/masters/master.tryserver.chromium.mac/slaves.cfg
index d7ca14d6aa7758e68639374b9d35ff59a4ebd536..eb5e0ea4148ad233b2811f769e78460f8a199783 100644
--- a/masters/master.tryserver.chromium.mac/slaves.cfg
+++ b/masters/master.tryserver.chromium.mac/slaves.cfg
@@ -44,8 +44,16 @@ def mac():
       'mac_chromium_variable_archive',
       'mac_chromium_variable_chrome',
       'mac_chromium_variable_gn',
+      'mac_chromium_variable_layout',
   ]
 
+  optional3_builders =  [
+      'mac_chromium_variable_10.10',
+      'mac_chromium_variable_10.10_layout',
+  ]
+
+  optional3_slaves = ['build%d-m4' % i for i in [190]]
+
   out = []
   out.extend(
     {
@@ -102,7 +110,18 @@ def mac():
       'bits': '64',
       'pool': 'mac_10_10',
     } for slave in ['build%d-m4' % i for i in xrange(158, 167)] +
-                   ['build%d-m4' % i for i in xrange(179, 190)]
+                   ['build%d-m4' % i for i in xrange(179, 189)]
+  )
+  out.extend(
+    {
+      'master': 'TryServerChromiumMac',
+      'builder': optional3_builders,
+      'hostname': slave,
+      'os': 'mac',
+      'version': '10.10',
+      'bits': '64',
+      'pool': 'mac_optional_10_10',
+    } for slave in optional3_slaves
   )
 
   return out