Introduce different repo types (git and gitiles)

unittests/repo_test_util.py

 # Copyright 2016 The LUCI Authors. All rights reserved.
 # Use of this source code is governed under the Apache License, Version 2.0
 # that can be found in the LICENSE file.
 
 """Utilities for testing with real repos (e.g. git)."""
 
 
 import contextlib
 import os
 import shutil
 import subprocess
 import sys
 import tempfile
 import unittest
 
 
 ROOT_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 sys.path.insert(0, os.path.join(ROOT_DIR, 'recipe_engine', 'third_party'))
 sys.path.insert(0, ROOT_DIR)
 
 
+from recipe_engine import fetch
 from recipe_engine import package
 from recipe_engine import package_pb2
 
 
 @contextlib.contextmanager
 def in_directory(target_dir):
   """Context manager that restores original working directory on exit."""
   old_dir = os.getcwd()
   os.chdir(target_dir)
   try:
@@ skipping 24 matching lines @@
       repo_root='bar',
       allow_fetch=False
     )
 
   def tearDown(self):
     shutil.rmtree(self._root_dir)
 
   def get_git_repo_spec(self, repo):
     """Returns GitRepoSpec corresponding to given repo."""
     return package.GitRepoSpec(
-        repo['name'], repo['root'], 'master', repo['revision'], '')
+        repo['name'],
+        repo['root'],
+        'master',
+        repo['revision'],
+        '',
+        fetch.GitBackend())
 
   def get_root_repo_spec(self, repo):
     """Returns RootRepoSpec corresponding to given repo."""
     config_file = os.path.join(repo['root'], 'infra', 'config', 'recipes.cfg')
     return package.RootRepoSpec(config_file)
 
   def get_package_spec(self, repo):
     """Returns PackageSpec corresponding to given repo."""
     config_file = os.path.join(repo['root'], 'infra', 'config', 'recipes.cfg')
     return package.PackageSpec.load_proto(package.ProtoFile(config_file))
@@ skipping 185 matching lines @@
       message = ' '.join(
         ['update %r recipe_module: ' % name] +
         ['%s(%s)' % t for t in methods.iteritems()]
       )
       return self.commit_in_repo(repo, message)
 
   def reset_repo(self, repo, revision):
     """Resets repo contents to given revision."""
     with in_directory(repo['root']):
       subprocess.check_output(['git', 'reset', '--hard', revision])