Don't send default cache header for 301 redirects

[e-moe]

Q	A
Branch?	"master"
Bug fix?	no
New feature?	yes
BC breaks?	yes
Deprecations?	no
Tests pass?	yes
Fixed tickets	#17139
License	MIT
Doc PR	see comments from #17139

[e-moe]

I'm not sure if it's correct place for this code. Looking forward for review

[fabpot]

I would instead move this into the main Response class just before sending the headers to the client.

[e-moe]

@fabpot, in Response class headers already computed and contains unnecessary 'no-cache' directive. We can't check wether is was set automatically or explicitly by user. see \Symfony\Component\HttpFoundation\ResponseHeaderBag::computeCacheControlValue

[e-moe]

probably we can add $withDefaultCacheControl parameter to \Symfony\Component\HttpFoundation\ResponseHeaderBag::__construct and do something like this:

/**
     * Constructor.
     *
     * @param array $headers An array of HTTP headers
     * @param bool $withDefaultCacheControl
     */
    public function __construct(array $headers = array(), $withDefaultCacheControl = true)
    {
        parent::__construct($headers);

        if ($withDefaultCacheControl && !isset($this->headers['cache-control'])) {
            $this->set('Cache-Control', '');
        }
    }

then, in Response constructor:

$this->headers = new ResponseHeaderBag($headers, 301 != $status); or, even better check against array like $this->headers = new ResponseHeaderBag($headers, in_array($status, self::$useDefaultCacheControl));

[fabpot]

I'm going to merge this as is.

[fabpot]

Thank you @e-moe.