Adds --skip-clear-data flag to android's test_runner.py

build/android/test_runner.py

 #!/usr/bin/env python
 #
 # Copyright 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.
 
 """Runs all types of tests from one unified interface."""
 
 import argparse
 import collections
@@ skipping 195 matching lines @@
                      help=('Target device for the test suite '
                            'to run on.'))
   group.add_argument('--blacklist-file', help='Device blacklist file.')
   group.add_argument('--enable-device-cache', action='store_true',
                      help='Cache device state to disk between runs')
   group.add_argument('--incremental-install', action='store_true',
                      help='Use an _incremental apk.')
   group.add_argument('--enable-concurrent-adb', action='store_true',
                      help='Run multiple adb commands at the same time, even '
                           'for the same device.')
+  group.add_argument('--skip-clear-data', action='store_true',
+                     help='Do not wipe app data between tests. Use this to '
+                     'speed up local development and never on bots '
+                     '(increases flakiness)')
 
 
 def AddGTestOptions(parser):
   """Adds gtest options to |parser|."""
 
   group = parser.add_argument_group('GTest Options')
   group.add_argument('-s', '--suite', dest='suite_name',
                      nargs='+', metavar='SUITE_NAME', required=True,
                      help='Executable name of the test suite to run.')
   group.add_argument('--gtest_also_run_disabled_tests',
@@ skipping 226 matching lines @@
       args.test_apk_path,
       args.test_apk_jar_path,
       args.test_runner,
       args.test_support_apk_path,
       args.device_flags,
       args.isolate_file_path,
       args.set_asserts,
       args.delete_stale_data,
       args.timeout_scale,
       args.apk_under_test,
-      args.additional_apks)
+      args.additional_apks,
+      args.skip_clear_data)
 
 
 def AddUIAutomatorTestOptions(parser):
   """Adds UI Automator test options to |parser|."""
 
   group = parser.add_argument_group('UIAutomator Test Options')
   AddJavaTestOptions(group)
   group.add_argument(
       '--package', required=True, choices=constants.PACKAGE_INFO.keys(),
       metavar='PACKAGE', help='Package under test.')
@@ skipping 620 matching lines @@
     if e.is_infra_error:
       return constants.INFRA_EXIT_CODE
     return constants.ERROR_EXIT_CODE
   except: # pylint: disable=W0702
     logging.exception('Unrecognized error occurred.')
     return constants.ERROR_EXIT_CODE
 
 
 if __name__ == '__main__':
   sys.exit(main())