[8.x] fix JsonResponse::fromJasonString() double encoding string

[alieffring]

The Illuminate\Http\JsonResponse class inherits a static fromJsonString() method from the base Symfony\Component\HttpFoundation\JsonResponse class for creating a JsonResponse from an already encoded JSON string, but because of changes to the constructor signature it does not perform as expected, returning a response with the provided string reencoded as a literal string. While you can achieve the desired result like so:

$response = new JsonResponse();
$response->setJson($jsonString);

(and that's probably the preferred way to do it anyway) it seems wrong to just leave the broken function there.

[taylorotwell]

Why did you need to redefine fromJsonString at all? Its method body is the same as the parent class so couldn't you just let the parent class define it?

[alieffring]

I hope I'm not missing something obvious, but the parent class method doesn't work because of the extra $options parameter that was added to the laravel implementation's constructor

return new static($data, $status, $headers, true); in the original
vs
return new static($data, $status, $headers, 0, true); in the new one

The test I added doesn't pass without the redefined fromJasonString.

[taylorotwell]

Ah, gotcha.