Issue #3510596: Boolean prop with false value is not defined

Closes #3510596

src/Element/ComponentElementBuilder.php

@@ -98,7 +98,7 @@ class ComponentElementBuilder implements TrustedCallbackInterface {
       }
     }
     else {
-      if (!empty($data) || $prop_type->getPluginId() === 'attributes') {
+      if (!empty($data) || in_array($prop_type->getPluginId(), ['attributes', 'boolean'])) {
         // For JSON Schema validator, empty value is not the same as missing
         // value, and we want to prevent some of the prop types rules to be
         // applied on empty values: string pattern, string format,
@@ -106,6 +106,8 @@ class ComponentElementBuilder implements TrustedCallbackInterface {
         // However, we don't remove empty attributes to avoid an error with
         // Drupal\Core\Template\TwigExtension::createAttribute() when themers
         // forget to use the default({}) filter.
+        // We do not remove empty value for boolean neither, because false is
+        // considered as empty, which is wrong.
         $build['#props'][$prop_or_slot_id] = $data;
       }
     }