MINOR Enforce SiteTree::$allowed_children in tree drag'n'drop for VirtualPage originals

admin/javascript/LeftAndMain.Tree.js

@@ -66,6 +66,9 @@
 											disallowedChildren = [],
 											hintKey = newParentClass ? newParentClass : 'Root',
 											hint = (typeof hints[hintKey] != 'undefined') ? hints[hintKey] : null;
+
+										// Special case for VirtualPage: Check that original page type is an allowed child
+										if(hint && movedNode.attr('class').match(/VirtualPage-([^\s]*)/)) movedNodeClass = RegExp.$1;
 										
 										if(hint) disallowedChildren = (typeof hint.disallowedChildren != 'undefined') ? hint.disallowedChildren : [];
 										var isAllowed = (