Work-around to make webkit test suite work with optdebug==2.

test/webkit/testcfg.py

 # Copyright 2013 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
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 91 matching lines @@
   def _IgnoreLine(self, string):
     """Ignore empty lines, valgrind output and Android output."""
     if not string: return True
     return (string.startswith("==") or string.startswith("**") or
             string.startswith("ANDROID") or
             # These five patterns appear in normal Native Client output.
             string.startswith("DEBUG MODE ENABLED") or
             string.startswith("tools/nacl-run.py") or
             string.find("BYPASSING ALL ACL CHECKS") > 0 or
             string.find("Native Client module will be loaded") > 0 or
-            string.find("NaClHostDescOpen:") > 0)
+            string.find("NaClHostDescOpen:") > 0 or
+            # FIXME(machenbach): The test driver shouldn't try to use slow
+            # asserts if they weren't compiled. This fails in optdebug=2.
+            string == "Warning: unknown flag --enable-slow-asserts." or
+            string == "Try --help for options")
 
   def IsFailureOutput(self, output, testpath):
     if super(WebkitTestSuite, self).IsFailureOutput(output, testpath):
       return True
     file_name = os.path.join(self.root, testpath) + "-expected.txt"
     with file(file_name, "r") as expected:
       expected_lines = expected.readlines()
 
     def ExpIterator():
       for line in expected_lines:
@@ skipping 27 matching lines @@
     for act_iterator in ActBlockIterator():
       for (expected, actual) in itertools.izip_longest(
           ExpIterator(), act_iterator, fillvalue=''):
         if expected != actual:
           return True
       return False
 
 
 def GetSuite(name, root):
   return WebkitTestSuite(name, root)