[TwigBridge] fixed form rendering when used in a template with dynamic inheritance
Merge branch '2.2' into 2.3

* 2.2:
  [HttpFoundation] removed double-slashes (closes #8388)
  [HttpFoundation] tried to keep the original Request URI as much as possible to avoid different behavior between ::createFromGlobals() and ::create()
  [TwigBridge] fixed form rendering when used in a template with dynamic inheritance