Constructor is not called in RegisterUser trait: Laravel 5.2

I have constructor in the trait RegistersUsers. We can find this trait in below mentioned path

vendor\laravel\framework\src\Illuminate\Foundation\Auth\RegistersUsers.php

Here the problem is, Constructor is not being called...Below is the code.

private function __construct( \App\Caching\CacheCollection $cacheData )
{
    $this->CacheCollection = $cacheData; 
}

Did somebody faced similar issue before ?

via Chebli Mohamed