Commits
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5c41ec9 [HttpKernel][Client] Only simple (name=value without any other params) cookies can be stored in same line, so lets add every as standalone to be compliant with rfc6265
Discussion
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[HttpKernel][Client] Set cookie fix
Bug fix: yes
Feature addition: no
Backwards compatibility break: no(?)
Symfony2 tests pass: yes
Fixes the following tickets: #2881
Only simple cookies can be stored in same line:
* Used by now (__wrong__): `Set-Cookie: name1=value, name2=value`
* Proper according to RFCs: `Set-Cookie: name1=value; name2=value`
So lets add every as standalone ([next header](http://tools.ietf.org/html/rfc6265#section-3.1)) to be compliant with [RFC6265](http://tools.ietf.org/html/rfc6265). This fixes#2881.