Move recipe engine to third_party/recipe_engine.

scripts/slave/recipe_modules/git_clone_bundler/api.py

 # Copyright 2015 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 hashlib
 
-from slave import recipe_api
+from recipe_engine import recipe_api
 
 """
 The 'git_clone_bundler' creates and uploads 'clone.bundle' packages to
 Google Storage for specified Git repositories.
 """
 
 class GitCloneBundlerApi(recipe_api.RecipeApi):
   """Provides methods to encapsulate repo operations."""
 
   def __init__(self, **kwargs):
@@ skipping 140 matching lines @@
       except self.m.step.StepFailure as e:
         result = self.m.step.active_result
         result.presentation.step_text = 'Exception: %s' % (e,)
         result.presentation.status = self.m.step.FAILURE
         errors.append(e)
 
     if errors:
       raise self.m.step.StepFailure("Encountered %d bundler failure(s)" % (
           len(errors,)))
     return bundle_map