Use tighter typing in editing/

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 183 matching lines @@
         position = firstEditableVisiblePositionAfterPositionInRoot(position, m_frame.document()->documentElement()).deepEquivalent();
         if (position.isNull())
             return;
 
         Position rangeCompliantPosition = position.parentAnchoredEquivalent();
         spellingSearchRange->setStart(rangeCompliantPosition.deprecatedNode(), rangeCompliantPosition.deprecatedEditingOffset(), IGNORE_EXCEPTION);
         startedWithSelection = false; // won't need to wrap
     }
 
     // topNode defines the whole range we want to operate on
-    Node* topNode = highestEditableRoot(position);
+    ContainerNode* topNode = highestEditableRoot(position);
     // FIXME: lastOffsetForEditing() is wrong here if editingIgnoresContent(highestEditableRoot()) returns true (e.g. a <table>)
     spellingSearchRange->setEnd(topNode, lastOffsetForEditing(topNode), IGNORE_EXCEPTION);
 
     // If spellingSearchRange starts in the middle of a word, advance to the next word so we start checking
     // at a word boundary. Going back by one char and then forward by a word does the trick.
     if (startedWithSelection) {
         VisiblePosition oneBeforeStart = startVisiblePosition(spellingSearchRange.get(), DOWNSTREAM).previous();
         if (oneBeforeStart.isNotNull())
             setStart(spellingSearchRange.get(), endOfWord(oneBeforeStart));
         // else we were already at the start of the editable node
@@ skipping 703 matching lines @@
 }
 
 void SpellChecker::requestTextChecking(const Element& element)
 {
     RefPtrWillBeRawPtr<Range> rangeToCheck = rangeOfContents(const_cast<Element*>(&element));
     m_spellCheckRequester->requestCheckingFor(SpellCheckRequest::create(TextCheckingTypeSpelling | TextCheckingTypeGrammar, TextCheckingProcessBatch, rangeToCheck, rangeToCheck));
 }
 
 
 } // namespace blink