Cast to array in upgrade foreach(). props arnee. fixes #5047

git-svn-id: https://develop.svn.wordpress.org/trunk@6158 602fd350-edb4-49c9-b593-d223f7449a82

wp-admin/includes/upgrade.php

@@ -1012,7 +1012,7 @@ function dbDelta($queries, $execute = true) {
 				}
 
 				// For every remaining index specified for the table
-				foreach($indices as $index) {
+				foreach ( (array) $indices as $index ) {
 					// Push a query line into $cqueries that adds the index to that table
 					$cqueries[] = "ALTER TABLE {$table} ADD $index";
 					$for_update[$table.'.'.$fieldname] = 'Added index '.$table.' '.$index;