bug #26584 [TwigBridge] allow html5 compatible rendering of forms wit…

…h null names (systemist)

This PR was submitted for the master branch but it was merged into the 2.7 branch instead (closes #26584).

Discussion
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[TwigBridge] allow html5 compatible rendering of forms with null names

Fixes html5 validation error with null form names.

Commits
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01c9e3c allow html5 compatible rendering of forms with null names

src/Symfony/Bridge/Twig/Resources/views/Form/form_div_layout.html.twig

@@ -275,7 +275,7 @@
     {%- else -%}
         {% set form_method = "POST" %}
     {%- endif -%}
-    <form name="{{ name }}" method="{{ form_method|lower }}" action="{{ action }}"{% for attrname, attrvalue in attr %} {{ attrname }}="{{ attrvalue }}"{% endfor %}{% if multipart %} enctype="multipart/form-data"{% endif %}>
+    <form{% if name != '' %} name="{{ name }}"{% endif %} method="{{ form_method|lower }}" action="{{ action }}"{% for attrname, attrvalue in attr %} {{ attrname }}="{{ attrvalue }}"{% endfor %}{% if multipart %} enctype="multipart/form-data"{% endif %}>
     {%- if form_method != method -%}
         <input type="hidden" name="_method" value="{{ method }}" />
     {%- endif -%}