item::random_query() doesn't need to take a "where" clause because

it's returning a query, so the caller can add the where clause
himself.  This makes for a cleaner API.

modules/gallery/helpers/item.php

@@ -209,17 +209,14 @@ static function root() {
 
   /**
    * Return a query to get a random Item_Model, with optional filters
-   *
-   * @param array   (optional) where tuple
    */
-  static function random_query($where=null) {
+  static function random_query() {
     // Pick a random number and find the item that's got nearest smaller number.
     // This approach works best when the random numbers in the system are roughly evenly
     // distributed so this is going to be more efficient with larger data sets.
     return ORM::factory("item")
       ->viewable()
       ->where("rand_key", "<", ((float)mt_rand()) / (float)mt_getrandmax())
-      ->merge_where($where)
       ->order_by("rand_key", "DESC");
   }
 }

modules/image_block/helpers/image_block_block.php

@@ -31,7 +31,7 @@ static function get($block_id, $theme) {
       // @todo Consider another fallback if further optimizations are necessary.
       $attempts = 0;
       do {
-        $item = item::random_query(array(array("type", "!=", "album")))->find_all(1)->current();
+        $item = item::random_query()->where("type", "!=", "album")->find_all(1)->current();
       } while (!$item && $attempts++ < 3);
       if ($item && $item->loaded()) {
         $block = new Block();