bug #35193 [TwigBridge] button_widget now has its title attr translated even if its label = null or false (stephen-lewis)

This PR was squashed before being merged into the 3.4 branch (closes #35193).

Discussion
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[TwigBridge] button_widget now has its title attr translated even if its label = null or false

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix #34330
| License       | MIT
| Doc PR        | TODO

Duplicate of #34436 but changed to bugfix and applied to 3.4. Buttons with null or false 'label' options will now have their 'title' attribute translated against the current translation domain.

Commits
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2a5d9cb75a [TwigBridge] button_widget now has its title attr translated even if its label = null or false

Author: fabpot

Resources/views/Form/form_div_layout.html.twig

@@ -222,13 +222,11 @@
                 '%name%': name,
                 '%id%': id,
             }) %}
-        {%- elseif label is same as(false) -%}
-            {% set translation_domain = false %}
-        {%- else -%}
+        {%- elseif label is not same as(false) -%}
             {% set label = name|humanize %}
         {%- endif -%}
     {%- endif -%}
-    <button type="{{ type|default('button') }}" {{ block('button_attributes') }}>{{ translation_domain is same as(false) ? label : label|trans({}, translation_domain) }}</button>
+    <button type="{{ type|default('button') }}" {{ block('button_attributes') }}>{{ translation_domain is same as(false) or label is same as(false) ? label : label|trans({}, translation_domain) }}</button>
 {%- endblock button_widget -%}
 
 {%- block submit_widget -%}