[tools/android] Replace FlagReplacer with flag_changer equivalent

tools/android/customtabs_benchmark/scripts/customtabs_benchmark.py

 #!/usr/bin/python
 #
 # Copyright 2015 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.
 
 """Loops Custom Tabs tests and outputs the results into a CSV file."""
 
 import collections
 import contextlib
 import logging
 import optparse
 import os
 import random
 import re
 import sys
 import time
 
 _SRC_PATH = os.path.abspath(os.path.join(
     os.path.dirname(__file__), os.pardir, os.pardir, os.pardir, os.pardir))
 
 sys.path.append(os.path.join(_SRC_PATH, 'third_party', 'catapult', 'devil'))
 from devil.android import device_errors
 from devil.android import device_utils
+from devil.android import flag_changer
 from devil.android.perf import cache_control
 from devil.android.sdk import intent
 
 sys.path.append(os.path.join(_SRC_PATH, 'build', 'android'))
 import devil_chromium
 
 sys.path.append(os.path.join(_SRC_PATH, 'tools', 'android', 'loading'))
 import chrome_setup
 import device_setup
 
@@ skipping 28 matching lines @@
       <first_contentful_paint>
     or None on error.
   """
   if not device.HasRoot():
     device.EnableRoot()
 
   timeout_s = 20
   logcat_timeout = int(timeout_s + delay_to_may_launch_url / 1000.
                        + delay_to_launch_url / 1000.) + 3;
 
-  with device_setup.FlagReplacer(device, _COMMAND_LINE_FILE, chrome_args):
+  with flag_changer.CustomCommandLineFlags(
+      device, _COMMAND_LINE_FILE, chrome_args):
     launch_intent = intent.Intent(
         action='android.intent.action.MAIN',
         package=_TEST_APP_PACKAGE_NAME,
         activity='org.chromium.customtabs.test.MainActivity',
         extras={'url': str(url), 'warmup': warmup,
                 'speculation_mode': str(speculation_mode),
                 'delay_to_may_launch_url': delay_to_may_launch_url,
                 'delay_to_launch_url': delay_to_launch_url,
                 'timeout': timeout_s})
     result_line_re = re.compile(r'CUSTOMTABSBENCH.*: (.*)')
@@ skipping 210 matching lines @@
       'delay_to_launch_url': options.delay_to_launch_url,
       'cold': options.cold,
   }
   LoopOnDevice(device, [config], options.output_file, options.wpr_archive,
                options.record, options.network_condition, options.wpr_log,
                once=options.once)
 
 
 if __name__ == '__main__':
   main()