Change notice: Replace all remaining superglobals ($_GET, $_POST, etc.) with Symfony Request object

In order to depend on using the Request object to determine caching, we need to ensure that everything uses it, rather than raw PHP variables for $_SERVER, $_REQUEST, $_GET, $_POST.

Conversion Guide

Remaining tasks: One last patch to remove all last $_GET, $_POST, $_COOKIE, $_REQUEST references. (Ignore $_SESSION for now, as it's being addressed elsewhere.)

Here are the methods on the Request object that map to PHP variables.

• $request->query The GET parameters
• $request->request The POST parameters
• $request->attributes The request attributes (parameters parsed from the PATH_INFO, ...)
• $request->cookies The COOKIE parameters
• $request->files The FILES parameters
• $request->server The SERVER parameters

See the Symfony documentation for an overview or a full list of convenience methods

• http://symfony.com/doc/current/components/http_foundation/introduction.html
• http://api.symfony.com/2.2/Symfony/Component/HttpFoundation/Request.html

To get the request object:

1. If it is a route controller method, you can add a Request parameter as the last param in the method signature, and it will magically be passed in
2. If you are in a new PSR-0, namespaced class, use \Drupal::request() (with a leading backslash)
3. If you are in old-skool functional land (e.g. includes) use Drupal::request() (without a leading backslash)

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