Merge branch '2.3' into 2.7

* 2.3:
  [HttpFoundation] Fix transient test
  [HttpFoundation] Add a dependency on the mbstring polyfill
  add readme files where missing
  Don't use reflections when possible
  [Form] Update form tests after the ICU data update
  [Intl] Update tests and the number formatter to match behaviour of the intl extension
  [Intl] Update the ICU data to version 55
  [Intl] Fix the update-data.php script in preparation for ICU 5.5
  Use constant instead of function call.
  fixed test name
  automatically generate safe fallback filename

Conflicts:
	src/Symfony/Component/Debug/Debug.php
	src/Symfony/Component/HttpFoundation/composer.json
	src/Symfony/Component/Serializer/Tests/Normalizer/GetSetMethodNormalizerTest.php

Author: nicolas-grekas

Container.php

@@ -356,9 +356,8 @@ public function initialized($id)
     public function getServiceIds()
     {
         $ids = array();
-        $r = new \ReflectionClass($this);
-        foreach ($r->getMethods() as $method) {
-            if (preg_match('/^get(.+)Service$/', $method->name, $match)) {
+        foreach (get_class_methods($this) as $method) {
+            if (preg_match('/^get(.+)Service$/', $method, $match)) {
                 $ids[] = self::underscore($match[1]);
             }
         }