Use wp_mkdir_p() to create js cache dir. Props DD32. see #6097

git-svn-id: http://svn.automattic.com/wordpress/trunk@7159 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/js/tinymce/tiny_mce_config.php

@@ -155,7 +155,7 @@ if ( $isIE5 ) $compress = false;
 // Cache path, this is where the .gz files will be stored
 $cache_path = ABSPATH . 'wp-content/uploads/js_cache'; 
 if ( $disk_cache && ! is_dir($cache_path) )
-	$disk_cache = mkdir($cache_path);
+	$disk_cache = wp_mkdir_p($cache_path);
 
 $cache_ext = '.js';