[FrameworkBundle][HttpKernel] Symfony esi handling allows objects to be passed as parameters

[asm89]

The framework has support for rendering "esi" tags. The internal implementation allows to pass objects as parameters of render standalone tags. This is a problem, because if you switch to a real reverse proxy, the objects in the parameters will be nullified.

I think this behavior should be changed to allow users to switch more transparently between a real reverse proxy and the symfony2 implementation.

The problem probably lies in the generation of the _internal uri. The code uses the http_build_query() method that will not include objects with no public fields: https://github.com/symfony/symfony/blob/master/src/Symfony/Bundle/FrameworkBundle/HttpKernel.php#L188. Parameters should only be scalars?

[lsmith77]

imho we have to leave it as is for 2.0, but should simply disallow any non scalar parameters in 2.1

[fabpot]

This has been reverted as they are some legitimate uses of passing an object directly like exception management.