Fix autoroller in accordance to upstream change

tools_webrtc/autoroller/unittests/roll_deps_test.py

 #!/usr/bin/env python
 # Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import glob
@@ skipping 64 matching lines @@
 
     self.fake = FakeCmd()
     self.old_run_command = getattr(roll_deps, '_RunCommand')
     setattr(roll_deps, '_RunCommand', self.fake)
 
   def tearDown(self):
     shutil.rmtree(self._output_dir, ignore_errors=True)
     self.assertEqual(self.fake.expectations, [])
     setattr(roll_deps, '_RunCommand', self.old_run_command)
 
+  def testVarLookup(self):
+    local_scope = {'foo': 'wrong', 'vars': {'foo': 'bar'}}
+    lookup = roll_deps.VarLookup(local_scope)
+    self.assertEquals(lookup('foo'), 'bar')
+
   def testUpdateDepsFile(self):
     new_rev = 'aaaaabbbbbcccccdddddeeeeefffff0000011111'
 
     current_rev = TEST_DATA_VARS['chromium_revision']
     UpdateDepsFile(self._webrtc_depsfile, current_rev, new_rev, [])
     with open(self._webrtc_depsfile) as deps_file:
       deps_contents = deps_file.read()
       self.assertTrue(new_rev in deps_contents,
                       'Failed to find %s in\n%s' % (new_rev, deps_contents))
 
@@ skipping 40 matching lines @@
     self.assertEquals(changed_deps[1].new_rev, BUILDTOOLS_NEW_REV)
 
 
 def _SetupGitLsRemoteCall(cmd_fake, url, revision):
   cmd = ['git', 'ls-remote', url, revision]
   cmd_fake.AddExpectation(cmd, _returns=(revision, None))
 
 
 if __name__ == '__main__':
   unittest.main()