Call NodeFilter.acceptNode() with correct this value

LayoutTests/fast/dom/TreeWalker/script-tests/acceptNode-filter.js

 description('Test JS objects as NodeFilters.');
 
 var walker;
 var testElement = document.createElement("div");
 testElement.id = 'root';
 testElement.innerHTML='<div id="A1"><div id="B1"></div><div id="B2"></div></div>';
 
 function filter(node)
 {
-    debug(" filtering node " + node.id);
+    debug(" filtering node " + node.id + " [this=" + this + "]");
     if (node.id == "B1")
         return NodeFilter.FILTER_SKIP;
     return NodeFilter.FILTER_ACCEPT;
 }
 
 debug("Testing with raw function filter");
 walker = document.createTreeWalker(testElement, NodeFilter.SHOW_ELEMENT, filter, false);
 shouldBe("walker.firstChild(); walker.currentNode.id", "'A1'");
 shouldBe("walker.nextNode(); walker.currentNode.id", "'B2'");
 
+function strictFilter(node)
+{
+    "use strict";
+    debug(" filtering node " + node.id + " [this=" + this + "]");
+    if (node.id == "B1")
+        return NodeFilter.FILTER_SKIP;
+    return NodeFilter.FILTER_ACCEPT;
+}
+
+debug("<br>Testing with strict raw function filter");
+walker = document.createTreeWalker(testElement, NodeFilter.SHOW_ELEMENT, strictFilter, false);
+shouldBe("walker.firstChild(); walker.currentNode.id", "'A1'");
+shouldBe("walker.nextNode(); walker.currentNode.id", "'B2'");
+
 debug("<br>Testing with object filter");
 walker = document.createTreeWalker(testElement, NodeFilter.SHOW_ELEMENT, {
+    toString : function() {
+      return "custom node filter";
+    },
     acceptNode : function(node) {
-      debug(" filtering node " + node.id);
+      debug(" filtering node " + node.id + " [this=" + this + "]");
       if (node.id == "B1")
           return NodeFilter.FILTER_SKIP;
       return NodeFilter.FILTER_ACCEPT;
     }
   }, false);
 
 shouldBe("walker.firstChild(); walker.currentNode.id", "'A1'");
 shouldBe("walker.nextNode(); walker.currentNode.id", "'B2'");
 
 debug("<br>Testing with null filter");
@@ skipping 35 matching lines @@
 debug("<br>Testing acceptNode callee");
 var filter = {
   acceptNode: function(node) {
     debug('Callee: ' + arguments.callee);
     return NodeFilter.FILTER_ACCEPT;
   }
 };
 walker = document.createTreeWalker(testElement, NodeFilter.SHOW_ELEMENT, filter, false);
 
 shouldBe("walker.firstChild(); walker.currentNode.id", "'A1'");