Introduce HasHTMLTagName functor and use it with ElementTraversal

Source/core/html/HTMLTableRowsCollection.cpp

 /*
  * Copyright (C) 2008, 2011, 2012, 2014 Apple Inc. All rights reserved.
  *
  * 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 82 matching lines @@
             if (HTMLTableRowElement* row = Traversal<HTMLTableRowElement>::firstChild(*child))
                 return row;
         }
     }
 
     return 0;
 }
 
 HTMLTableRowElement* HTMLTableRowsCollection::lastRow(HTMLTableElement& table)
 {
-    for (HTMLElement* child = Traversal<HTMLElement>::lastChild(table); child; child = Traversal<HTMLElement>::previousSibling(*child)) {
-        if (child->hasTagName(tfootTag)) {
-            if (HTMLTableRowElement* lastRow = Traversal<HTMLTableRowElement>::lastChild(*child))
+    for (HTMLElement* tfoot = Traversal<HTMLElement>::lastChild(table, HasHTMLTagName(tfootTag)); tfoot; tfoot = Traversal<HTMLElement>::previousSibling(*tfoot, HasHTMLTagName(tfootTag))) {
+        if (HTMLTableRowElement* lastRow = Traversal<HTMLTableRowElement>::lastChild(*tfoot))
                 return lastRow;
-        }
     }
 
     for (HTMLElement* child = Traversal<HTMLElement>::lastChild(table); child; child = Traversal<HTMLElement>::previousSibling(*child)) {
         if (isHTMLTableRowElement(child))
             return toHTMLTableRowElement(child);
         if (child->hasTagName(tbodyTag)) {
             if (HTMLTableRowElement* lastRow = Traversal<HTMLTableRowElement>::lastChild(*child))
                 return lastRow;
         }
     }
 
-    for (HTMLElement* child = Traversal<HTMLElement>::lastChild(table); child; child = Traversal<HTMLElement>::previousSibling(*child)) {
-        if (child->hasTagName(theadTag)) {
-            if (HTMLTableRowElement* lastRow = Traversal<HTMLTableRowElement>::lastChild(*child))
-                return lastRow;
-        }
+    for (HTMLElement* thead = Traversal<HTMLElement>::lastChild(table, HasHTMLTagName(theadTag)); thead; thead = Traversal<HTMLElement>::previousSibling(*thead, HasHTMLTagName(theadTag))) {
+        if (HTMLTableRowElement* lastRow = Traversal<HTMLTableRowElement>::lastChild(*thead))
+            return lastRow;
     }
 
     return 0;
 }
 
 // Must call get() on the table in case that argument is compiled before dereferencing the
 // table to get at the collection cache. Order of argument evaluation is undefined and can
 // differ between compilers.
 HTMLTableRowsCollection::HTMLTableRowsCollection(ContainerNode& table)
     : HTMLCollection(table, TableRows, OverridesItemAfter)
 {
     ASSERT(isHTMLTableElement(table));
 }
 
 PassRefPtrWillBeRawPtr<HTMLTableRowsCollection> HTMLTableRowsCollection::create(ContainerNode& table, CollectionType type)
 {
     ASSERT_UNUSED(type, type == TableRows);
     return adoptRefWillBeNoop(new HTMLTableRowsCollection(table));
 }
 
 Element* HTMLTableRowsCollection::virtualItemAfter(Element* previous) const
 {
     return rowAfter(toHTMLTableElement(ownerNode()), toHTMLTableRowElement(previous));
 }
 
 }