Use new is*Element() helper functions in DOM code

Source/core/dom/ScriptLoader.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nikolas Zimmermann <zimmermann@kde.org>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 263 matching lines @@
 
     if (m_resource)
         return true;
 
     dispatchErrorEvent();
     return false;
 }
 
 bool isHTMLScriptLoader(Element* element)
 {
-    return element->hasTagName(HTMLNames::scriptTag);
+    ASSERT(element);
+    return isHTMLScriptElement(*element);

[eseidel, 2014/03/10 18:17:01]

Won't dereferencing null on the next line crash just the same as the ASSERT
would?

[Inactive, 2014/03/10 18:21:54]

I would prefer hitting an assertion than actually crashing. In any case, I will
likely further refactor this in a follow-up so that isHTMLScriptLoader() takes a
reference in parameter. I just want to keep the change small.

Having this assert in place makes it very obvious the argument is expected to be
non-null and can become a reference.

 }
 
 bool isSVGScriptLoader(Element* element)
 {
-    return element->hasTagName(SVGNames::scriptTag);
+    ASSERT(element);
+    return isSVGScriptElement(*element);
 }
 
 void ScriptLoader::executeScript(const ScriptSourceCode& sourceCode)
 {
     ASSERT(m_alreadyStarted);
 
     if (sourceCode.isEmpty())
         return;
 
     RefPtr<Document> elementDocument(m_element->document());
@@ skipping 135 matching lines @@
     if (isHTMLScriptLoader(element))
         return toHTMLScriptElement(element)->loader();
 
     if (isSVGScriptLoader(element))
         return toSVGScriptElement(element)->loader();
 
     return 0;
 }
 
 }