Increase test runner speed.

tools/run-tests.py

 #!/usr/bin/env python
 #
 # Copyright 2012 the V8 project authors. 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.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 275 matching lines @@
   workspace = os.path.abspath(join(os.path.dirname(sys.argv[0]), ".."))
   if not options.no_presubmit:
     print ">>> running presubmit tests"
     code = subprocess.call(
         [sys.executable, join(workspace, "tools", "presubmit.py")])
     exit_code = code
 
   suite_paths = utils.GetSuitePaths(join(workspace, "test"))
 
   if len(args) == 0:
-    suite_paths = [ s for s in suite_paths if s in DEFAULT_TESTS ]
+    suite_paths = [ s for s in DEFAULT_TESTS if s in suite_paths ]
   else:
     args_suites = set()
     for arg in args:
       suite = arg.split(os.path.sep)[0]
       if not suite in args_suites:
         args_suites.add(suite)
-    suite_paths = [ s for s in suite_paths if s in args_suites ]
+    suite_paths = [ s for s in args_suites if s in suite_paths ]
 
   suites = []
   for root in suite_paths:
     suite = testsuite.TestSuite.LoadTestSuite(
         os.path.join(workspace, "test", root))
     if suite:
       suites.append(suite)
 
   if options.download_data:
     for s in suites:
@@ skipping 120 matching lines @@
   except KeyboardInterrupt:
     return 1
 
   if options.time:
     verbose.PrintTestDurations(suites, overall_duration)
   return exit_code
 
 
 if __name__ == "__main__":
   sys.exit(Main())