MINOR Adjusted to changed TreeNodeAPI->setNodeIcon() arguments - usin…

…g 'class-' prefix to denote PHP classes in the tree DOM now

git-svn-id: svn://svn.silverstripe.com/silverstripe/open/modules/sapphire/trunk@92532 467b73ca-7a2a-4603-9d3b-597d59a354a9

core/model/SiteTree.php

@@ -2243,7 +2243,7 @@ public function Level($level) {
 	 * @return string
 	 */
 	function CMSTreeClasses($controller) {
-		$classes = $this->class;
+		$classes = sprintf('class-%s', $this->class);
 		if($this->HasBrokenFile || $this->HasBrokenLink)
 			$classes .= " BrokenLink";