fixed detection of secure cookies received over https

BrowserKit's cookie handling only recognises a secure cookie if the
cookie option is set and the cookie was set over an https request.
The client was not passing the url into the cookiejar update code,
causing Cookie::isSecure() to always return false for every cookie.

Fixes symfony/symfony#7666
[BrowserKit] removed dead code
[HttpFoundation][BrowserKit] fixed path when converting a cookie to a string

An empty path has a different meaning than a /; it means that the path
is the one from the current URI.
Merge branch '2.1' into 2.2

* 2.1:
  [HttpFoundation][BrowserKit] fixed path when converting a cookie to a string
  [BrowserKit] removed dead code
  [HttpFoundation] fixed empty domain= in Cookie::__toString()
  fixed detection of secure cookies received over https
  [Translation] removed an uneeded class property
  [Translation] removed unneeded getter/setter
  [Translator] added additional conversion for encodings other than utf-8
  fix a DI circular reference recognition bug
  [HttpFoundation] fixed the creation of sub-requests under some circumstances for IIS
[BrowserKit] fixed BC break done recently
Merge branch '2.1' into 2.2

* 2.1:
  [BrowserKit] fixed BC break done recently
  [Process] Fix #5594 : `termsig` must be used instead of `stopsig` in exceptions when a process is signaled
  Rename misprint property (from warmer to finder)
  Add This field is missing RU translation

Conflicts:
	src/Symfony/Component/Process/Process.php
	src/Symfony/Component/Validator/Resources/translations/validators.ru.xlf