Merge branch '2.6' into 2.7

* 2.6:
  Added 'default' color
  [HttpFoundation] Reload the session after regenerating its id
  [HttpFoundation] Add a test case to confirm a bug in session migration
  [2.6] Static Code Analysis for Components and Bundles
  [Finder] Command::addAtIndex() fails with Command instance argument
  [DependencyInjection] Freeze also FrozenParameterBag::remove
  [Twig][Bridge] replaced `extends` with `use` in bootstrap_3_horizontal_layout.html.twig
  fix CS
  fixed CS
  Add a way to reset the singleton
  [Security] allow to use `method` in XML configs
  Remove duplicate example
  Remove var not used due to returning early (introduced in 8982c32)
  Enhance hhvm test skip message

Tests/FormTest.php

@@ -825,7 +825,6 @@ public function testFormRegistrySetValueOnCompoundField()
      */
     public function testFormRegistrySetArrayOnNotCompoundField()
     {
-
         $registry = new FormFieldRegistry();
         $registry->add($this->getFormFieldMock('bar'));