[Android] Prepare build/android/ for catapult+devil.

build/android/pylib/instrumentation/test_jar.py

 # Copyright (c) 2013 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.
 
 """Helper class for instrumenation test jar."""
 # pylint: disable=W0702
 
 import logging
 import os
 import pickle
 import re
-import sys
 
 from devil.android import device_utils
 from devil.android import md5sum
 from pylib import constants
+from pylib.constants import host_paths
 from pylib.utils import proguard
 
-sys.path.insert(0,
-                os.path.join(constants.DIR_SOURCE_ROOT,
-                             'build', 'util', 'lib', 'common'))
-
-import unittest_util # pylint: disable=F0401
+with host_paths.SysPath(host_paths.BUILD_COMMON_PATH):
+  import unittest_util # pylint: disable=import-error
 
 # If you change the cached output of proguard, increment this number
 PICKLE_FORMAT_VERSION = 4
 
 
 class TestJar(object):
   _ANNOTATIONS = frozenset(
       ['Smoke', 'SmallTest', 'MediumTest', 'LargeTest', 'EnormousTest',
        'FlakyTest', 'DisabledTest', 'Manual', 'PerfTest', 'HostDrivenTest',
        'IntegrationTest'])
@@ skipping 199 matching lines @@
     devices = device_utils.DeviceUtils.parallel(devices)
     min_sdk_version = min(devices.build_version_sdk.pGet(None))
     tests = [t for t in tests
              if self._IsTestValidForSdkRange(t, min_sdk_version)]
 
     return tests
 
   @staticmethod
   def IsHostDrivenTest(test):
     return 'pythonDrivenTests' in test