[5.4] Fix the way the request post parameters are set

[dan-har]

On request creation, the post parameters bag if filled with query parameters on any
request that is not json. This change fix that, and only json request content will be
parsed and added to the request post parameters.

[sisve]

Are you sure? getInputSource checks the http method; and the existing code should also handle the json case.

[taylorotwell]

I don't really see a problem with the current behavior.

[dan-har]

@sisve @taylorotwell

While I was working on integration of a legacy code project with illuminate http request, I've notice that request is sent without content but the $request->request parameters bag has values. That behvior was not expected so I've override the createFromBase function with the change in this commit to make it work as expected.

The current behavior creates a GET request object with empty content but override the $request->request with the query parameters. The problem is that the request object suggests that there is content on the request and that is a worng behavior.

The current behvior in code is:

$request->query->all() == $request->request->all()
$request->getContent() == ''

and I would expect

$request->request->all() == []
$request->getContent() == ''

Hope that explains it in better way.