Add swarming support for MB (and the GN bots) in the chromium recipes.

scripts/slave/recipe_modules/chromium_tests/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.
 
 import contextlib
 import copy
 import json
 
 from infra.libs.infra_types import freeze, thaw
 from recipe_engine import recipe_api
@@ skipping 109 matching lines @@
         except self.m.step.StepFailure:
           # As part of deapplying patch we call runhooks without the patch.
           self.deapply_patch(update_step)
           raise
       else:
         self.m.chromium.runhooks()
 
     test_spec_file = bot_config.get('testing', {}).get('test_spec_file',
                                                        '%s.json' % mastername)
 
-    if self.m.chromium.c.project_generator.tool == 'mb':
-      self.m.chromium.run_mb(mastername, buildername)
-
     # TODO(phajdan.jr): Bots should have no generators instead.
     if bot_config.get('disable_tests'):
       test_spec = {}
       scripts_compile_targets = {}
     else:
       test_spec = self.read_test_spec(self.m, test_spec_file)
       test_spec_path = self.m.path['checkout'].join('testing', 'buildbot',
                                                  test_spec_file)
 
       scripts_compile_targets = \
@@ skipping 165 matching lines @@
 
     bot_config = master_dict.get('builders', {}).get(buildername)
     master_config = master_dict.get('settings', {})
     bot_type = override_bot_type or bot_config.get('bot_type', 'builder_tester')
 
     self.m.chromium.cleanup_temp()
     if self.m.chromium.c.TARGET_PLATFORM == 'android':
       self.m.chromium_android.clean_local_files()
       self.m.chromium_android.run_tree_truth()
 
+    if self.m.chromium.c.project_generator.tool == 'mb':
+      self.m.chromium.run_mb(mastername, buildername, swarming_targets=[
+          t.name for t in tests_including_triggered if t.uses_swarming])
+
     if bot_type in ['builder', 'builder_tester']:
       isolated_targets = [
         t.isolate_target for t in tests_including_triggered if t.uses_swarming
       ]
 
       if isolated_targets:
         self.m.isolate.clean_isolated_files(self.m.chromium.output_dir)
 
       self.transient_check(update_step, lambda transform_name:
         self.m.chromium.compile(compile_targets,
@@ skipping 346 matching lines @@
   def get_compile_targets_for_scripts(self):
     return self.m.python(
         name='get compile targets for scripts',
         script=self.m.path['checkout'].join(
             'testing', 'scripts', 'get_compile_targets.py'),
         args=[
             '--output', self.m.json.output(),
             '--',
         ] + self.get_common_args_for_scripts(),
         step_test_data=lambda: self.m.json.test_api.output({}))