Merge branch '2.3' into 2.6

* 2.3:
  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

Author: fabpot

Definition/Builder/ExprBuilder.php

@@ -224,7 +224,7 @@ public function end()
     public static function buildExpressions(array $expressions)
     {
         foreach ($expressions as $k => $expr) {
-            if ($expr instanceof ExprBuilder) {
+            if ($expr instanceof self) {
                 $if = $expr->ifPart;
                 $then = $expr->thenPart;
                 $expressions[$k] = function ($v) use ($if, $then) {

Loader/FileLoader.php

@@ -82,7 +82,7 @@ public function import($resource, $type = null, $ignoreErrors = false, $sourceRe
         try {
             $loader = $this->resolve($resource, $type);
 
-            if ($loader instanceof FileLoader && null !== $this->currentDir) {
+            if ($loader instanceof self && null !== $this->currentDir) {
                 // we fallback to the current locator to keep BC
                 // as some some loaders do not call the parent __construct()
                 // @deprecated should be removed in 3.0