[FrameworkBundle] Fixed OutOfBoundException when session handler_id is null

When a null is provided for framework.session.handler_id the FrameworkExtension attempts to set the session storage to null for the 'session.storage.php_bridge' by altering the second argument. According to the session.xml service definition, there is no second argument, and it is in fact the first (read, 0 index) argument that should be changed.
Merge branch '2.3'

* 2.3: (33 commits)
  Revert "[Console] ensure exit code between 0-254"
  Added missing galician (gl) translations
  fix many-to-many Propel1 ModelChoiceList
  [Console] ensure exit code between 0-254
  Added Greek translation
  [DomCrawler] Fixed a fatal error when setting a value in a malformed field name.
  [FrameworkBundle] Fixed OutOfBoundException when session handler_id is null
  [DependencyInjection] Add support for aliases of aliases + regression test
  [Console] fix status code when Exception::getCode returns something like 0.1
  Fixed doc block on Filesystem::rename
  Fixed exit code for exceptions with error code 0
  [DependencyInjection] Rename ContainerBuilder::$aliases to avoid conflicting with the parent class
  [DependencyInjection] Remove get*Alias*Service methods from compiled containers
  [DependencyInjection] Fix aliased access of shared services, fixes #8096
  instantiate valid commands only
  bumped Symfony version to -DEV
  updated VERSION for 2.3.0
  updated CHANGELOG for 2.3.0
  [Config] Added tests for the FileResource and DirectoryResource.
  [Config] Fixed @covers annotation which ignored some of the methods from the code coverage.
  ...

Conflicts:
	src/Symfony/Component/HttpKernel/Kernel.php