Merge branch '3.4' into 4.4

* 3.4:
  Remove branch-version (keep them for contracts only)
  [Serializer] fix decoding float XML attributes starting with 0
  add missing dutch translations
  [Validator] Add missing romanian translations
  do not translate null placeholders or titles

Resources/views/Form/form_div_layout.html.twig

@@ -444,7 +444,7 @@
     {%- for attrname, attrvalue in attr -%}
         {{- " " -}}
         {%- if attrname in ['placeholder', 'title'] -%}
-            {{- attrname }}="{{ translation_domain is same as(false) ? attrvalue : attrvalue|trans(attr_translation_parameters, translation_domain) }}"
+            {{- attrname }}="{{ translation_domain is same as(false) or attrvalue is null ? attrvalue : attrvalue|trans(attr_translation_parameters, translation_domain) }}"
         {%- elseif attrvalue is same as(true) -%}
             {{- attrname }}="{{ attrname }}"
         {%- elseif attrvalue is not same as(false) -%}

composer.json

@@ -78,8 +78,5 @@
             "/Tests/"
         ]
     },
-    "minimum-stability": "dev",
-    "extra": {
-        "branch-version": "4.4"
-    }
+    "minimum-stability": "dev"
 }