Coding Standards: Always use parentheses when instantiating an object.

Note: This will be enforced by WPCS 3.0.0.

Props jrf.
See #56791.

git-svn-id: https://develop.svn.wordpress.org/trunk@54891 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-user.php

@@ -156,7 +156,7 @@ class WP_User {
 		if ( $data ) {
 			$this->init( $data, $site_id );
 		} else {
-			$this->data = new stdClass;
+			$this->data = new stdClass();
 		}
 	}