Use always_run v can_fail_build

scripts/slave/recipe_modules/step/api.py

 # Copyright 2013 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.
 
 from slave import recipe_api
 
 class StepApi(recipe_api.RecipeApi):
   def __init__(self, *args, **kwargs):
     self._auto_resolve_conflicts = False
     self._name_function = None
@@ skipping 18 matching lines @@
       name: The name of this step.
       cmd: A list of strings in the style of subprocess.Popen.
       **kwargs: Additional entries to add to the annotator.py step dictionary.
 
     Returns:
       A step dictionary which is compatible with annotator.py.
     """
     assert 'shell' not in kwargs
     assert isinstance(cmd, list)
 
+    if kwargs.get('abort_on_failure', False):
+      @recipe_api.wrap_followup(kwargs)
+      def assert_success(step_result):
+        if step_result.presentation.status == 'FAILURE':
+          raise recipe_api.RecipeAbort(
+            "Step(%s) failed and was marked as abort_on_failure" % name)
+      kwargs['followup_fn'] = assert_success
+
     cmd = list(cmd)  # Create a copy in order to not alter the input argument.
     if self.auto_resolve_conflicts:
       step_count = self._step_names.setdefault(name, 0) + 1
       self._step_names[name] = step_count
       if step_count > 1:
         name = "%s (%d)" % (name, step_count)
     ret = kwargs
     ret.update({'name': name, 'cmd': cmd})
     return ret