Refactor infra git libs and testing.

test.py

Index: test.py
diff --git a/test.py b/test.py
new file mode 100755
index 0000000000000000000000000000000000000000..e25a86bd93164190e38997681f5922d48ded5850
--- /dev/null
+++ b/test.py
@@ -0,0 +1,15 @@
+#!/usr/bin/env python
+# Copyright 2014 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.
+
+"""Convenience script for (cd [infra] && ENV/bin/expect_tests "$@")"""
+
+assert __name__ == '__main__'
+
+import os
+import sys
+
+path = os.path.join('ENV', 'bin', 'expect_tests')
+os.chdir(os.path.dirname(__file__))
+os.execv(path, [path] + sys.argv[1:])