[READ-ONLY] Subtree split of the Symfony EventDispatcher Component
Latest commit e8f47a3 Oct 13, 2016 @nicolas-grekas nicolas-grekas Merge branch '3.1'
* 3.1:
  [travis] Test on PHP 7.1
  simplified code
  Remove unused variable
  3.0 Upgrade Guide: Added Table of Contents
  [HttpFoundation] add missing upgrade entry
  [FrameworkBundle] Convert null prefix to an empty string in translation:update command
  Improved the deprecation messages for service aliases
  [Serializer] minor: Remove an extra space in a YamlFileLoader error
  [HttpKernel] Clean ArgumentMetadataFactory::getType()
  [PropertyInfo] Fix edge cases in ReflectionExtractor