Add Android-backend to the memory_inspector (prerequisites).

tools/memory_inspector/tests/core_test.py

 #!/usr/bin/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.
 
+"""Unittests for the core backends modules."""
+
 import logging
 import os
 import sys
 import unittest
 
 sys.path.append(os.path.abspath(os.path.join(__file__, os.pardir, os.pardir)))
 
 from memory_inspector.core import backends
 from memory_inspector.core import memory_map
 from memory_inspector.core import stacktrace
@@ skipping 88 matching lines @@
     st.Add(frame_2)
     st.Add(frame_1)
     self.assertEqual(st.depth, 4)
 
 
 if __name__ == '__main__':
   logging.basicConfig(
       level=logging.DEBUG if '-v' in sys.argv else logging.ERROR,
       format='%(levelname)5s %(filename)15s(%(lineno)3d): %(message)s')
   unittest.main()