Use new is*Element() helper functions even more in HTML code

Source/core/html/HTMLEmbedElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Stefan Schimanski (1Stein@gmx.de)
  * Copyright (C) 2004, 2005, 2006, 2008, 2009, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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 36 matching lines @@
 
 PassRefPtr<HTMLEmbedElement> HTMLEmbedElement::create(Document& document, bool createdByParser)
 {
     RefPtr<HTMLEmbedElement> element = adoptRef(new HTMLEmbedElement(document, createdByParser));
     element->ensureUserAgentShadowRoot();
     return element.release();
 }
 
 static inline RenderWidget* findWidgetRenderer(const Node* n)
 {
-    if (!n->renderer())
-        do
+    if (!n->renderer()) {
+        do {
             n = n->parentNode();
-        while (n && !n->hasTagName(objectTag));
+        } while (n && !isHTMLObjectElement(*n));
+    }
 
     if (n && n->renderer() && n->renderer()->isWidget())
         return toRenderWidget(n->renderer());
 
     return 0;
 }
 
 RenderWidget* HTMLEmbedElement::existingRenderWidget() const
 {
     return findWidgetRenderer(this);
@@ skipping 96 matching lines @@
     if (isImageType())
         return HTMLPlugInElement::rendererIsNeeded(style);
 
     LocalFrame* frame = document().frame();
     if (!frame)
         return false;
 
     // If my parent is an <object> and is not set to use fallback content, I
     // should be ignored and not get a renderer.
     ContainerNode* p = parentNode();
-    if (p && p->hasTagName(objectTag)) {
+    if (isHTMLObjectElement(p)) {
         ASSERT(p->renderer());
         if (!toHTMLObjectElement(p)->useFallbackContent()) {
             ASSERT(!p->renderer()->isEmbeddedObject());
             return false;
         }
     }
     return HTMLPlugInElement::rendererIsNeeded(style);
 }
 
 bool HTMLEmbedElement::isURLAttribute(const Attribute& attribute) const
 {
     return attribute.name() == srcAttr || HTMLPlugInElement::isURLAttribute(attribute);
 }
 
 const AtomicString HTMLEmbedElement::imageSourceURL() const
 {
     return getAttribute(srcAttr);
 }
 
 bool HTMLEmbedElement::isInteractiveContent() const
 {
     return true;
 }
 
 bool HTMLEmbedElement::isExposed() const
 {
     // http://www.whatwg.org/specs/web-apps/current-work/#exposed
     for (Node* ancestor = parentNode(); ancestor; ancestor = ancestor->parentNode()) {
-        if (ancestor->hasTagName(objectTag) && toHTMLObjectElement(ancestor)->isExposed())
+        if (isHTMLObjectElement(*ancestor) && toHTMLObjectElement(*ancestor).isExposed())
             return false;
     }
     return true;
 }
 
 }