adding fix for empty search query

inc/roots-cleanup.php

@@ -21,6 +21,17 @@ function roots_search_query($escaped = true) {
 
 add_filter('get_search_query', 'roots_search_query');
 
+// fix for empty search query
+// http://wordpress.org/support/topic/blank-search-sends-you-to-the-homepage#post-1772565
+function roots_request_filter($query_vars) {
+    if(isset($_GET['s']) && empty($_GET['s'])) {
+        $query_vars['s'] = " ";
+    }
+    return $query_vars;
+}
+
+add_filter('request', 'roots_request_filter');
+
 // root relative URLs for everything
 // inspired by http://www.456bereastreet.com/archive/201010/how_to_make_wordpress_urls_root_relative/
 // thanks to Scott Walkinshaw (scottwalkinshaw.com)