Merge branch '2.3' into 2.7

* 2.3:
  added missing quotes in YAML files
  [HttpKernel] Add `@group time-sensitive` on some transient tests
  [DoctrineBridge] Fix issue which prevent the profiler to explain a query
  Use mb_detect_encoding with $strict = true
  don't allow to install the split Security packages
  bumped Symfony version to 2.3.35
  updated VERSION for 2.3.34
  update CONTRIBUTORS for 2.3.34
  updated CHANGELOG for 2.3.34

Author: fabpot

Extension/Core/DataTransformer/NumberToLocalizedStringTransformer.php

@@ -197,7 +197,7 @@ public function reverseTransform($value)
             throw new TransformationFailedException('I don\'t have a clear idea what infinity looks like');
         }
 
-        if (function_exists('mb_detect_encoding') && false !== $encoding = mb_detect_encoding($value)) {
+        if (function_exists('mb_detect_encoding') && false !== $encoding = mb_detect_encoding($value, null, true)) {
             $length = mb_strlen($value, $encoding);
             $remainder = mb_substr($value, $position, $length, $encoding);
         } else {