Change run_webkit_tests default order to random on Linux and Mac

third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/run_webkit_tests.py

 # Copyright (C) 2010 Google Inc. All rights reserved.
 # Copyright (C) 2010 Gabor Rapcsanyi (rgabor@inf.u-szeged.hu), University of Szeged
 # Copyright (C) 2011 Apple Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
@@ skipping 311 matching lines @@
                 default=0,
                 help="Set the maximum number of locked shards"),
             optparse.make_option(
                 "--nocheck-sys-deps",
                 action="store_true",
                 default=False,
                 help="Don't check the system dependencies (themes)"),
             optparse.make_option(
                 "--order",
                 action="store",
-                default="natural",
+                # TODO(jeffcarp): platforms are moving to random-order by default independently.
+                # See _set_up_derived_options below and crbug.com/601332.
+                default=("default"),
                 help=("Determine the order in which the test cases will be run. "
                       "'none' == use the order in which the tests were listed "
                       "either in arguments or test list, "
-                      "'natural' == use the natural order (default), "
                       "'random' == pseudo-random order. Seed can be specified "
-                      "via --seed, otherwise it will default to the current unix timestamp.")),
+                      "via --seed, otherwise it will default to the current unix timestamp "
+                      "(default on Mac & Linux). "
+                      "'natural' == use the natural order (default on all others).")),
             optparse.make_option(
                 "--profile",
                 action="store_true",
                 help="Output per-test profile information."),
             optparse.make_option(
                 "--profiler",
                 action="store",
                 help="Output per-test profile information, using the specified profiler."),
             optparse.make_option(
                 "--repeat-each",
@@ skipping 191 matching lines @@
         options.skipped = 'default'
 
     if 'GTEST_SHARD_INDEX' in port.host.environ and 'GTEST_TOTAL_SHARDS' in port.host.environ:
         shard_index = int(port.host.environ['GTEST_SHARD_INDEX']) + 1
         total_shards = int(port.host.environ['GTEST_TOTAL_SHARDS']) + 1
         options.run_part = '{0}:{1}'.format(shard_index, total_shards)
 
     if not options.seed:
         options.seed = port.host.time()
 
+    # TODO(jeffcarp): This will be removed once all platforms move to random order.
+    # This must be here and not in parse_args because host is not instantiated yet there.
+    # See crbug.com/601332.
+    if options.order == 'default':
+        port_name = port.host.port_factory.get().port_name
+        if port_name.startswith(("linux-", "mac-")):
+            options.order = 'random'
+        else:
+            options.order = 'natural'
+
 def _run_tests(port, options, args, printer):
     _set_up_derived_options(port, options, args)
     manager = Manager(port, options, printer)
     printer.print_config(port.results_directory())
     return manager.run(args)
 
 
 def run(port, options, args, logging_stream, stdout):
     logger = logging.getLogger()
     logger.setLevel(logging.DEBUG if options.debug_rwt_logging else logging.INFO)
@@ skipping 26 matching lines @@
             _log.debug("\t%s", process)
 
         return run_details
 
     finally:
         printer.cleanup()
 
 if __name__ == '__main__':
     exit_code = main(sys.argv[1:], sys.stdout, sys.stderr)
     sys.exit(exit_code)