Remove null check on refNode in Range::comparePoint

Source/core/dom/Range.cpp

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * (C) 2000 Gunnstein Lye (gunnstein@netcom.no)
  * (C) 2000 Frederik Holljen (frederik.holljen@hig.no)
  * (C) 2001 Peter Kelly (pmk@post.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Motorola Mobility. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 227 matching lines @@
     return compareBoundaryPoints(refNode, offset, m_start.container(), m_start.offset(), exceptionState) >= 0 && !exceptionState.hadException()
         && compareBoundaryPoints(refNode, offset, m_end.container(), m_end.offset(), exceptionState) <= 0 && !exceptionState.hadException();
 }
 
 short Range::comparePoint(Node* refNode, int offset, ExceptionState& exceptionState) const
 {
     // http://developer.mozilla.org/en/docs/DOM:range.comparePoint
     // This method returns -1, 0 or 1 depending on if the point described by the
     // refNode node and an offset within the node is before, same as, or after the range respectively.
 
-    if (!refNode) {
-        exceptionState.throwDOMException(HierarchyRequestError, "The node provided was null.");
-        return 0;
-    }
-
     if (!refNode->inActiveDocument()) {
         exceptionState.throwDOMException(WrongDocumentError, "The node provided is not in an active document.");
         return 0;
     }
 
     if (refNode->document() != m_ownerDocument) {
         exceptionState.throwDOMException(WrongDocumentError, "The node provided is not in this Range's Document.");
         return 0;
     }
 
@@ skipping 1446 matching lines @@
 
 void showTree(const blink::Range* range)
 {
     if (range && range->boundaryPointsValid()) {
         range->startContainer()->showTreeAndMark(range->startContainer(), "S", range->endContainer(), "E");
         fprintf(stderr, "start offset: %d, end offset: %d\n", range->startOffset(), range->endOffset());
     }
 }
 
 #endif