Revert of Cross-repo recipe package system.

scripts/slave/recipe_modules/git/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.
 
-import itertools
 import re
 
 from recipe_engine import recipe_api
 
 class GitApi(recipe_api.RecipeApi):
   _GIT_HASH_RE = re.compile('[0-9a-f]{40}', re.IGNORECASE)
 
   def __call__(self, *args, **kwargs):
     """Return a git command step."""
     name = kwargs.pop('name', 'git '+args[0])
@@ skipping 237 matching lines @@
       rev_parse_step = self('rev-parse', 'HEAD',
                            cwd=dir_path,
                            name='set got_revision',
                            stdout=self.m.raw_io.output(),
                            can_fail_build=False)
 
       if rev_parse_step.presentation.status == 'SUCCESS':
         sha = rev_parse_step.stdout.strip()
         rev_parse_step.presentation.properties['got_revision'] = sha
 
-    clean_args = list(itertools.chain(
+    clean_args = list(self.m.itertools.chain(
         *[('-e', path) for path in keep_paths or []]))
 
     self('clean', '-f', '-d', '-x', *clean_args,
       name='git clean%s' % step_suffix,
       cwd=dir_path,
       can_fail_build=can_fail_build)
 
     if submodules:
       self('submodule', 'sync',
         name='submodule sync%s' % step_suffix,
@@ skipping 68 matching lines @@
 
     Args:
       bundle_path (Path): The path of the output bundle.
       refs (list): The list of refs to include in the bundle. If None, all
           refs in the Git checkout will be bundled.
       kwargs: Forwarded to '__call__'.
     """
     if not rev_list_args:
       rev_list_args = ['--all']
     self('bundle', 'create', bundle_path, *rev_list_args, **kwargs)