HTMLTableElement.insertRow()'s argument default value should be -1

Source/core/html/HTMLTableElement.cpp

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008, 2010, 2011 Apple Inc. 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 163 matching lines @@
 
 HTMLTableSectionElement* HTMLTableElement::lastBody() const
 {
     for (Node* child = lastChild(); child; child = child->previousSibling()) {
         if (child->hasTagName(tbodyTag))
             return toHTMLTableSectionElement(child);
     }
     return 0;
 }
 
+PassRefPtrWillBeRawPtr<HTMLElement> HTMLTableElement::insertRow(ExceptionState& exceptionState)
+{
+    // The default 'index' argument value is -1.
+    return insertRow(-1, exceptionState);
+}
+
 PassRefPtrWillBeRawPtr<HTMLElement> HTMLTableElement::insertRow(int index, ExceptionState& exceptionState)
 {
     if (index < -1) {
         exceptionState.throwDOMException(IndexSizeError, "The index provided (" + String::number(index) + ") is less than -1.");
         return nullptr;
     }
 
     RefPtrWillBeRawPtr<Node> protectFromMutationEvents(this);
 
     RefPtrWillBeRawPtr<HTMLTableRowElement> lastRow = nullptr;
@@ skipping 378 matching lines @@
     return getAttribute(summaryAttr);
 }
 
 void HTMLTableElement::trace(Visitor* visitor)
 {
     visitor->trace(m_sharedCellStyle);
     HTMLElement::trace(visitor);
 }
 
 }