Support sharding for swarmed isolated script tests.

scripts/slave/recipe_modules/chromium_tests/steps.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 re
 import string
 
 
 class Test(object):
   """
@@ skipping 1208 matching lines @@
     browser_config = api.chromium.c.build_config_fs.lower()
     args = self._args[:]
 
     # TODO(nednguyen): only rerun the tests that failed for the "without patch"
     # suffix.
 
     # For the time being, we assume all isolated_script_test are not idempotent
     # TODO(nednguyen): make this configurable in isolated_scripts's spec.
     return api.swarming.isolated_script_task(
         title=self._step_name(suffix), isolated_hash=isolated_hash,
-        idempotent=False, extra_args=args)
+        shards=self._shards, idempotent=False, extra_args=args)
 
   def validate_task_results(self, api, step_result):
     results = getattr(step_result, 'isolated_script_results', None) or {}
 
     try:
       failures = results['failures']
       valid = results['valid']
       if not failures and step_result.retcode != 0:
         failures = ['%s (entire test suite)' % self.name]
         valid = False
@@ skipping 621 matching lines @@
   def run(self, api, suffix, test_filter=None):
     api.chromium_android.coverage_report(upload=False)
     api.chromium_android.get_changed_lines_for_revision()
     api.chromium_android.incremental_coverage_report()
 
 
 GOMA_TESTS = [
   GTestTest('base_unittests'),
   GTestTest('content_unittests'),
 ]