[5.2] Reverse a breaking addition in Route.php

[themsaid]

In an earlier PR #12899, controller routes were included in the Route:middleware() method output by calling ControllerDispatcher, this had two effects:

1. All middlewares registered inside the controller's constructor will be executed twice, once from ControllerDispatcher::callWithinStack() when the controller is actually being dispatched and another in Router::runRouteWithinStack() while the Router is dispatching the request to the route.
2. All code inside the controller constructor will be executed while the ControllerDispatcher is instantiating the controller, some of this code is considered protected by a middleware registered in routes.php.

For example a code inside the controller constructor that logs a user's presence inside the dashboard area, this code will be executed although the controller is protected under the auth controller for example, or auth.type.admin

Also calls to Request::user() && Auth::user() will return null if the user is not logged in, although the developer added the auth middleware to this controller inside the routes file, this will call a PHP error when Controller dispatches is called instead of executing the auth middleware and redirect the user to the log in screen.

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Terminable middlewares are useful, however I say we keep the old behaviour of firing them only when registered otherwhere than the controller for 5.2 in order not to break things.

And I suggest in 5.3 we remove the Controller::middleware() method and make people use a static method for example that we can run from outside to collect the middlewares without executing the constructor code.

And since we will be already collecting controller middlewares data before firing the controller actions, we won't need to read the controller routes from inside the controller itself.