Introduce toHTMLInputElement(Node*), and use it.

Source/core/rendering/HitTestResult.cpp

 /*
  * Copyright (C) 2006, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2012 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 227 matching lines @@
 {
     if (!m_innerNonSharedNode)
         return String();
     
     if (m_innerNonSharedNode->hasTagName(imgTag)) {
         HTMLImageElement* image = static_cast<HTMLImageElement*>(m_innerNonSharedNode.get());
         return displayString(image->getAttribute(altAttr), m_innerNonSharedNode.get());
     }
     
     if (m_innerNonSharedNode->hasTagName(inputTag)) {
-        HTMLInputElement* input = static_cast<HTMLInputElement*>(m_innerNonSharedNode.get());
+        HTMLInputElement* input = toHTMLInputElement(m_innerNonSharedNode.get());
         return displayString(input->alt(), m_innerNonSharedNode.get());
     }
 
     return String();
 }
 
 Image* HitTestResult::image() const
 {
     if (!m_innerNonSharedNode)
         return 0;
@@ skipping 109 matching lines @@
 // hooks into it. Anyway, we should architect this better. 
 bool HitTestResult::isContentEditable() const
 {
     if (!m_innerNonSharedNode)
         return false;
 
     if (m_innerNonSharedNode->hasTagName(textareaTag))
         return true;
 
     if (m_innerNonSharedNode->hasTagName(inputTag))
-        return static_cast<HTMLInputElement*>(m_innerNonSharedNode.get())->isTextField();
+        return toHTMLInputElement(m_innerNonSharedNode.get())->isTextField();
 
     return m_innerNonSharedNode->rendererIsEditable();
 }
 
 bool HitTestResult::addNodeToRectBasedTestResult(Node* node, const HitTestRequest& request, const HitTestLocation& locationInContainer, const LayoutRect& rect)
 {
     // If it is not a rect-based hit test, this method has to be no-op.
     // Return false, so the hit test stops.
     if (!isRectBasedTest())
         return false;
@@ skipping 85 matching lines @@
 {
     for (Node* node = m_innerNode.get(); node; node = node->parentNode()) {
         if (node->isElementNode())
             return toElement(node);
     }
 
     return 0;
 }
 
 } // namespace WebCore