Merge branch '5.2' into 5.x

* 5.2:
  merge translation parameters with value configured for parent form
  scan directories for translations sequentially
  Fix kafka tests
  Fix "provide" declarations
  Provide implemented packages of replaced dependencies
  Always autoload string functions on symfony/symfony

Author: nicolas-grekas

composer.json

@@ -42,7 +42,7 @@
     },
     "provide": {
         "psr/container-implementation": "1.0",
-        "symfony/service-implementation": "1.0"
+        "symfony/service-implementation": "1.0|2.0"
     },
     "autoload": {
         "psr-4": { "Symfony\\Component\\DependencyInjection\\": "" },