Ensure mjsunit tests use dashes not underscores in flags directives.

tools/presubmit.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 85 matching lines @@
 whitespace/newline
 whitespace/operators
 whitespace/parens
 whitespace/tab
 whitespace/todo
 """.split()
 
 # TODO(bmeurer): Fix and re-enable readability/check
 
 LINT_OUTPUT_PATTERN = re.compile(r'^.+[:(]\d+[:)]|^Done processing')
-
+FLAGS_LINE = re.compile("//\s*Flags:.*--([A-z0-9-])+_[A-z0-9].*\n")
 
 def CppLintWorker(command):
   try:
     process = subprocess.Popen(command, stderr=subprocess.PIPE)
     process.wait()
     out_lines = ""
     error_count = -1
     while True:
       out_line = process.stderr.readline()
       if out_line == '' and process.poll() != None:
@@ skipping 290 matching lines @@
         line += 1
       if len(lines) >= 1:
         linenumbers = ', '.join(lines)
         if len(lines) > 1:
           print "%s does not have two empty lines between declarations " \
                 "in lines %s." % (name, linenumbers)
         else:
           print "%s does not have two empty lines between declarations " \
                 "in line %s." % (name, linenumbers)
         result = False
+    # Sanitize flags for fuzzer.
+    if "mjsunit" in name:
+      match = FLAGS_LINE.search(contents)
+      if match:
+        print "%s Flags should use '-' (not '_')" % name
+        result = False
     return result
 
   def ProcessFiles(self, files, path):
     success = True
     violations = 0
     for file in files:
       try:
         handle = open(file)
         contents = handle.read()
         if not self.ProcessContents(file, contents):
@@ skipping 65 matching lines @@
   success = CheckRuntimeVsNativesNameClashes(workspace) and success
   success = CheckExternalReferenceRegistration(workspace) and success
   if success:
     return 0
   else:
     return 1
 
 
 if __name__ == '__main__':
   sys.exit(Main())