IBX-3092: dropdown in subfield should be small like other fields (#479)

* IBX-3092: Dropdown in subfields should have small size

* Do not render ibexa-form-error when form is valid

src/bundle/Resources/views/themes/admin/content/form_fields.html.twig

@@ -49,7 +49,10 @@
 
     {% set label_attr = label_attr|merge({'class': (label_attr.class|default('') ~ ' ibexa-label ibexa-data-source__label ibexa-data-source__label')|trim}) %}
     {% set label_wrapper_attr = label_wrapper_attr|default({})|merge({'class': (label_wrapper_attr.class|default('') ~ ' ibexa-data-source__label-wrapper ibexa-data-source__label-wrapper')|trim}) %}
-    {% set attr = attr|merge({'class': (attr.class|default('') ~ ' ibexa-data-source__input ibexa-data-source__input ibexa-input--small')|trim}) %}
+    {% set attr = attr|merge({
+        class: (attr.class|default('') ~ ' ibexa-data-source__input ibexa-data-source__input ibexa-input--small')|trim,
+        is_small: true,
+    }) %}
     {% set wrapper_attr = wrapper_attr|default({})|merge({class: (wrapper_attr.class|default('') ~ ' ' ~ wrapper_class)|trim}) %}
     {% set widget_wrapper_attr = widget_wrapper_attr|default({})|merge({class: (widget_wrapper_attr.class|default('') ~ ' ibexa-data-source__input-wrapper ibexa-data-source__input-wrapper')|trim}) %}
 
@@ -62,9 +65,11 @@
         <div{% with { attr: widget_wrapper_attr } %}{{ block('attributes') }}{% endwith %}>
             {{- form_widget(form, {'attr': attr}) -}}
         </div>
-        <div class="ibexa-form-error">
-            {{- block('form_errors') -}}
-        </div>
+        {% if form.vars.errors|length > 0 %}
+            <div class="ibexa-form-error">
+                {{- block('form_errors') -}}
+            </div>
+        {% endif %}
     </div>
 {%- endblock %}