[Android] Clean up gtest filtering logic.

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.
 
 TODO(gkanwar):
 * Add options to run Monkey tests.
@@ skipping 108 matching lines @@
     cmd_helper.OutDirectory.set(options.out_directory)
   run_tests_helper.SetLogLevel(options.verbose_count)
 
 
 def AddCoreGTestOptions(option_parser, default_timeout=60):
   """Add options specific to the gtest framework to |option_parser|."""
 
   # TODO(gkanwar): Consolidate and clean up test filtering for gtests and
   # content_browsertests.
   option_parser.add_option('--gtest_filter', dest='test_filter',
-                           help='Filter GTests by name.')
+                           help='googletest-style filter string.')
   option_parser.add_option('-a', '--test_arguments', dest='test_arguments',
                            help='Additional arguments to pass to the test.')
   # TODO(gkanwar): Most likely deprecate/remove this option once we've pinned
   # down what we're doing with the emulator setup.
   option_parser.add_option('-x', '--xvfb', dest='use_xvfb',
                            action='store_true',
                            help='Use Xvfb around tests (ignored if not Linux).')
   # TODO(gkanwar): Possible deprecate this flag. Waiting on word from Peter
   # Beverloo.
   option_parser.add_option('--webkit', action='store_true',
@@ skipping 386 matching lines @@
     return 0
   command = argv[1]
   VALID_COMMANDS[command].add_options_func(option_parser)
   options, args = option_parser.parse_args(argv)
   return VALID_COMMANDS[command].run_command_func(
       command, options, args, option_parser)
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))