Update middleware reference.

app/Http/Middleware/AuthenticatedWithBasicAuth.php

-<?php namespace App\Http\Middleware;
-
-use Closure;
-use Illuminate\Contracts\Auth\Guard;
-use Illuminate\Contracts\Routing\Middleware;
-
-class AuthenticatedWithBasicAuth implements Middleware {
-
-	/**
-	 * The Guard implementation.
-	 *
-	 * @var Guard
-	 */
-	protected $auth;
-
-	/**
-	 * Create a new filter instance.
-	 *
-	 * @param  Guard  $auth
-	 * @return void
-	 */
-	public function __construct(Guard $auth)
-	{
-		$this->auth = $auth;
-	}
-
-	/**
-	 * Handle an incoming request.
-	 *
-	 * @param  \Illuminate\Http\Request  $request
-	 * @param  \Closure  $next
-	 * @return mixed
-	 */
-	public function handle($request, Closure $next)
-	{
-		return $this->auth->basic() ?: $next($request);
-	}
-
-}

app/Providers/RouteServiceProvider.php

@@ -12,7 +12,7 @@ class RouteServiceProvider extends ServiceProvider {
 	 */
 	protected $middleware = [
 		'auth' => 'App\Http\Middleware\Authenticated',
-		'auth.basic' => 'App\Http\Middleware\AuthenticatedWithBasicAuth',
+		'auth.basic' => 'Illuminate\Auth\Middleware\AuthenticatedWithBasicAuth',
 		'guest' => 'App\Http\Middleware\IsGuest',
 	];