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

Source/core/editing/SpellChecker.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 37 matching lines @@
 
 namespace WebCore {
 
 using namespace HTMLNames;
 
 namespace {
 
 bool isSelectionInTextField(const VisibleSelection& selection)
 {
     HTMLTextFormControlElement* textControl = enclosingTextFormControl(selection.start());
-    return textControl && textControl->hasTagName(inputTag) && toHTMLInputElement(textControl)->isTextField();
+    return isHTMLInputElement(textControl) && toHTMLInputElement(textControl)->isTextField();
 }
 
 } // namespace
 
 PassOwnPtr<SpellChecker> SpellChecker::create(LocalFrame& frame)
 {
     return adoptPtr(new SpellChecker(frame));
 }
 
 static SpellCheckerClient& emptySpellCheckerClient()
@@ skipping 52 matching lines @@
         bool isTextField = false;
         HTMLTextFormControlElement* enclosingHTMLTextFormControlElement = 0;
         if (!isHTMLTextFormControlElement(*element))
             enclosingHTMLTextFormControlElement = enclosingTextFormControl(firstPositionInNode(element));
         element = enclosingHTMLTextFormControlElement ? enclosingHTMLTextFormControlElement : element;
         Element* parent = element;
         if (isHTMLTextFormControlElement(*element)) {
             HTMLTextFormControlElement* textControl = toHTMLTextFormControlElement(element);
             parent = textControl;
             element = textControl->innerTextElement();
-            isTextField = textControl->hasTagName(inputTag) && toHTMLInputElement(textControl)->isTextField();
+            isTextField = isHTMLInputElement(*textControl) && toHTMLInputElement(*textControl).isTextField();
         }
 
         if (isTextField || !parent->isAlreadySpellChecked()) {
             // We always recheck textfields because markers are removed from them on blur.
             VisibleSelection selection = VisibleSelection::selectionFromContentsOfNode(element);
             markMisspellingsAndBadGrammar(selection);
             if (!isTextField)
                 parent->setAlreadySpellChecked(true);
         }
     }
@@ skipping 703 matching lines @@
 }
 
 void SpellChecker::requestTextChecking(const Element& element)
 {
     RefPtr<Range> rangeToCheck = rangeOfContents(const_cast<Element*>(&element));
     m_spellCheckRequester->requestCheckingFor(SpellCheckRequest::create(TextCheckingTypeSpelling | TextCheckingTypeGrammar, TextCheckingProcessBatch, rangeToCheck, rangeToCheck));
 }
 
 
 } // namespace WebCore