Ticket #3476: 3476.patch

_source/core/dom/domwalker.js

@@ -31 +31 @@
                                 if ( !current )
                                         return null;
 
-                                if ( current.getChildCount() > 0 )
+                                if ( current.getChildCount && current.getChildCount() > 0 )
                                 {
                                         next = current.getChild( 0 );
                                         fireDomWalkerEvent.call( this, 'down', current, next );
@@ -90 +90 @@
                                 {
                                         var lastChild = current.getPrevious();
                                         fireDomWalkerEvent.call( this, 'sibling', current, lastChild );
-                                        while ( lastChild.getChildCount() > 0 )
+                                        while ( lastChild.getChildCount && lastChild.getChildCount() > 0 )
                                         {
                                                 next = lastChild.getChild( lastChild.getChildCount() - 1 );
                                                 fireDomWalkerEvent.call( this, 'down', lastChild, next );