Description:
------------
When ReflectionClass::implementsInterface receives a trait as a parameter the message of the thrown exception says that the trait is a class.

Test script:
---------------
<?php
trait T {}

try {
    (new ReflectionClass(new stdClass))->implementsInterface(T::class);
} catch (ReflectionException $e) {
    echo $e->getMessage();
}

Expected result:
----------------
T is not an interface

Actual result:
--------------
Interface T is a Class