Convert swarm_triggered to OS specific builder.

projects.py

Index: projects.py
diff --git a/projects.py b/projects.py
index b10bbff52ef4eccd815f654ccf0878c8ef7f6f11..a32085bd2a626020dd1fb00d7782b1c5db2ab84f 100644
--- a/projects.py
+++ b/projects.py
@@ -414,9 +414,9 @@ def _gen_chromium(user, root_dir, rietveld_obj, no_try):
     # Commenting out the items below will make the CQ not use swarm for its
     # execution. Uncomment to make the CQ use Swarming again.
     swarm_enabled_builders_and_tests = {
-      #'linux_rel': swarm_test_map,
-      # 'mac_rel': swarm_test_map,
-      # 'win_rel': swarm_test_map,
+      ('linux_rel', 'linux_swarm_triggered'): swarm_test_map,
+      # ('mac_rel', 'mac_swarm_triggered'): swarm_test_map,
+      # ('win_rel', 'win_swarm_triggered'): swarm_test_map,
     }
 
     step_verifiers += [
@@ -435,14 +435,14 @@ def _gen_chromium(user, root_dir, rietveld_obj, no_try):
     ]
 
     # Add the swarm enabled builders with swarm accepted tests.
-    for builder, builder_swarm_enabled_tests in (
+    for (builder, triggered), builder_swarm_enabled_tests in (
         swarm_enabled_builders_and_tests.iteritems()):
       regular_tests = list(set(builders_and_tests[builder]) -
                            set(builder_swarm_enabled_tests))
 
       step_verifiers.append(
           try_job_steps.TryJobTriggeredOrNormalSteps(
-              builder_name='swarm_triggered',
+              builder_name=triggered,
               trigger_name=builder,
               prereq_builder=prereq_builder,
               prereq_tests=prereq_tests,