Merge branch '2.6' into 2.7

* 2.6:
  [Translator] Cache does not take fallback locales into consideration
  [VarDumper] Fix call site detection
  [Process] Fix volatile test
  Remove some useless @group annotations
  Removed useless strtolower call
  [Validator] Use strict comparisons in loaders
  CS: Use "self" keyword instead of class name if possible

Conflicts:
	.travis.yml
	src/Symfony/Component/Translation/Translator.php

Author: fabpot

Acl/Domain/RoleSecurityIdentity.php

@@ -52,7 +52,7 @@ public function getRole()
      */
     public function equals(SecurityIdentityInterface $sid)
     {
-        if (!$sid instanceof RoleSecurityIdentity) {
+        if (!$sid instanceof self) {
             return false;
         }
 

Acl/Domain/UserSecurityIdentity.php

@@ -102,7 +102,7 @@ public function getClass()
      */
     public function equals(SecurityIdentityInterface $sid)
     {
-        if (!$sid instanceof UserSecurityIdentity) {
+        if (!$sid instanceof self) {
             return false;
         }