Update from https://crrev.com/305340

build/android/pylib/constants.py

 # Copyright (c) 2012 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.
 
 """Defines a set of constants shared by test runners and other scripts."""
 # pylint: disable=W0212
 
 import collections
 import logging
 import os
@@ skipping 169 matching lines @@
 
 UPSTREAM_FLAKINESS_SERVER = 'test-results.appspot.com'
 
 DEVICE_LOCAL_PROPERTIES_PATH = '/data/local.prop'
 
 PYTHON_UNIT_TEST_SUITES = {
   'pylib_py_unittests': {
     'path': os.path.join(DIR_SOURCE_ROOT, 'build', 'android'),
     'test_modules': [
       'pylib.device.device_utils_test',
+      'pylib.utils.md5sum_test',
     ]
   },
   'gyp_py_unittests': {
     'path': os.path.join(DIR_SOURCE_ROOT, 'build', 'android', 'gyp'),
     'test_modules': [
       'java_cpp_enum_tests',
     ]
   },
 }
 
@@ skipping 39 matching lines @@
 def _Memoize(func):
   def Wrapper():
     try:
       return func._result
     except AttributeError:
       func._result = func()
       return func._result
   return Wrapper
 
 
+def SetAdbPath(adb_path):
+  os.environ['ADB_PATH'] = adb_path
+
+
+def GetAdbPath():
+  # Check if a custom adb path as been set. If not, try to find adb
+  # on the system.
+  if os.environ.get('ADB_PATH'):
+    return os.environ.get('ADB_PATH')
+  else:
+    return _FindAdbPath()
+
+
 @_Memoize
-def GetAdbPath():
+def _FindAdbPath():
   if os.environ.get('ANDROID_SDK_ROOT'):
     return 'adb'
   # If envsetup.sh hasn't been sourced and there's no adb in the path,
   # set it here.
   try:
     with file(os.devnull, 'w') as devnull:
       subprocess.call(['adb', 'version'], stdout=devnull, stderr=devnull)
     return 'adb'
   except OSError:
     logging.debug('No adb found in $PATH, fallback to checked in binary.')
     return os.path.join(ANDROID_SDK_ROOT, 'platform-tools', 'adb')
 
-
 # Exit codes
 ERROR_EXIT_CODE = 1
 WARNING_EXIT_CODE = 88