Add isolate.clean_isolated_files and use in all related recipes.

scripts/slave/recipes/swarming/canary.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.
 
 """Swarming canary recipe: runs tests for HEAD of chromium using HEAD of
 swarming_client toolset on Swarming canary server instances (*-dev.appspot.com).
 
 Intended to catch bugs in swarming_client and Swarming servers early on, before
 full roll out.
 
@@ skipping 43 matching lines @@
   if not step_result.json.output['did_run']:
     api.gclient.checkout()
 
   # Ensure swarming_client version is fresh enough.
   api.swarming.check_client_version()
 
   # Build all supported tests, isolate them to the server. Set ISOLATE_DEBUG so
   # that isolate scripts invoked by ninja produce more information. Corresponds
   # to --profile flag.
   api.chromium.runhooks()
+  api.isolate.clean_isolated_files(api.chromium.output_dir)
   api.chromium.compile(
       targets=['chromium_swarm_tests'], env={'ISOLATE_DEBUG': 1})
 
   # Gather hashes of all isolated tests.
   api.isolate.find_isolated_tests(api.chromium.output_dir)
 
   # Make swarming tasks that run isolated tests.
   tasks = [
     api.swarming.gtest_task(
         test,
@@ skipping 23 matching lines @@
 
 def GenTests(api):
   for platform in ('linux', 'win', 'mac'):
     for configuration in ('Debug', 'Release'):
       yield (
         api.test('%s_%s' % (platform, configuration)) +
         api.platform.name(platform) +
         api.properties.scheduled() +
         api.properties(configuration=configuration)
       )