Add code style check error for using static_cast instead of toFoo function.

Tools/Scripts/webkitpy/style/checkers/cpp_unittest.py

 # -*- coding: utf-8; -*-
 #
 # Copyright (C) 2011 Google Inc. All rights reserved.
 # Copyright (C) 2009 Torch Mobile Inc.
 # Copyright (C) 2009 Apple Inc. All rights reserved.
 # Copyright (C) 2010 Chris Jerdonek (cjerdonek@webkit.org)
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
@@ skipping 746 matching lines @@
     def test_runtime_rtti(self):
         statement = 'int* x = dynamic_cast<int*>(&foo);'
         error_message = (
             'Do not use dynamic_cast<>.  If you need to cast within a class '
             'hierarchy, use static_cast<> to upcast.  Google doesn\'t support '
             'RTTI.  [runtime/rtti] [5]')
         # dynamic_cast is disallowed in most files.
         self.assert_language_rules_check('foo.cpp', statement, error_message)
         self.assert_language_rules_check('foo.h', statement, error_message)
 
-    # Test for static_cast readability.
-    def test_static_cast_readability(self):
+    # Tests for static_cast readability.
+    def test_use_toFoo_readability(self):
         self.assert_lint(
             'Text* x = static_cast<Text*>(foo);',
-            'Consider using toText helper function in WebCore/dom/Text.h '
-            'instead of static_cast<Text*>'
+            'static_cast of class objects is not allowed. Use toText defined in Text.h.'
+            '  [readability/check] [4]')
+
+    def test_create_and_use_toFoo_readability(self):
+        self.assert_lint(
+            'HTMLButtonElement* x = static_cast<HTMLButtonElement*>(foo);',
+            'static_cast of class objects is not allowed. Add toHTMLButtonElement in HTMLButtonElement.h and use it instead.'
             '  [readability/check] [4]')
 
     # We cannot test this functionality because of difference of
     # function definitions.  Anyway, we may never enable this.
     #
     # # Test for unnamed arguments in a method.
     # def test_check_for_unnamed_params(self):
     #   message = ('All parameters should be named in a function'
     #              '  [readability/function] [3]')
     #   self.assert_lint('virtual void A(int*) const;', message)
@@ skipping 4368 matching lines @@
     def test_ne(self):
         """Test __ne__ inequality function."""
         checker1 = self._checker()
         checker2 = self._checker()
 
         # != calls __ne__.
         # By default, __ne__ always returns true on different objects.
         # Thus, just check the distinguishing case to verify that the
         # code defines __ne__.
         self.assertFalse(checker1 != checker2)