Move recipe engine to third_party/recipe_engine.

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 re
 
-from slave import recipe_api
+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])
     if 'cwd' not in kwargs:
       kwargs.setdefault('cwd', self.m.path['checkout'])
     git_cmd = 'git'
@@ skipping 319 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)