Fail build if triggering fails

scripts/slave/recipe_modules/trigger/api.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """This recipe module allows triggering builds within the same master.
 
 See README.md.
 """
 
 from recipe_engine import recipe_api
@@ skipping 20 matching lines @@
 
   def __call__(self, *trigger_specs, **kwargs):
     """Triggers new builds by builder names.
 
     Args:
       trigger_specs: a list of trigger dicts, where each dict specifies a build
         to trigger. Supported keys:
           builder_name (str): in BuildBot context, builder name
           bucket (str): buildbucket bucket where the triggered builds will be
             placed.
+          critical (bool): if True (default) and triggering fails on the
+            buildbot master side, mark entire build as failed (exception).
           properties (dict): build properties for a new build.
           buildbot_changes (list of dict): list of Buildbot changes to create.
             See below.
           tags (dict or list of str): if the trigger build is scheduled through
             buildbucket, |tags| will be appended to the buildbucket build.
       name: name of the step. If not specified, it is generated
         automatically. Its format may change in future.
 
     Buildbot changes:
       buildbot_changes (a list of dicts) is a list of changes for the
@@ skipping 72 matching lines @@
         assert key != 'parent_build_id', 'parent_build_id tag is reserved'
 
     result = self.m.step(
         kwargs.get('name', 'trigger'),
         cmd=[],
         trigger_specs=trigger_specs,
     )
     if 'name' not in kwargs:
       result.presentation.step_text = "<br />".join(sorted(builder_names))
     return result