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

Source/core/html/HTMLAnchorElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Simon Hausmann <hausmann@kde.org>
  * Copyright (C) 2003, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * 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 153 matching lines @@
 }
 
 static void appendServerMapMousePosition(StringBuilder& url, Event* event)
 {
     if (!event->isMouseEvent())
         return;
 
     ASSERT(event->target());
     Node* target = event->target()->toNode();
     ASSERT(target);
-    if (!target->hasTagName(imgTag))
+    if (!isHTMLImageElement(*target))
         return;
 
-    HTMLImageElement* imageElement = toHTMLImageElement(event->target()->toNode());
-    if (!imageElement || !imageElement->isServerMap())
+    HTMLImageElement& imageElement = toHTMLImageElement(*target);
+    if (!imageElement.isServerMap())
         return;
 
-    if (!imageElement->renderer() || !imageElement->renderer()->isRenderImage())
+    if (!imageElement.renderer() || !imageElement.renderer()->isRenderImage())
         return;
-    RenderImage* renderer = toRenderImage(imageElement->renderer());
+    RenderImage* renderer = toRenderImage(imageElement.renderer());
 
     // FIXME: This should probably pass true for useTransforms.
     FloatPoint absolutePosition = renderer->absoluteToLocal(FloatPoint(toMouseEvent(event)->pageX(), toMouseEvent(event)->pageY()));
     int x = absolutePosition.x();
     int y = absolutePosition.y();
     url.append('?');
     url.appendNumber(x);
     url.append(',');
     url.appendNumber(y);
 }
@@ skipping 499 matching lines @@
     preconnectToURL(url, motivation);
     m_hasIssuedPreconnect = true;
 }
 
 bool HTMLAnchorElement::isInteractiveContent() const
 {
     return isLink();
 }
 
 }