Issue #3474822 by pdureau, sea2709, smustgrave, just_like_good_vibes: Normalize attributes values

Closes #3474822

src/Element/ComponentElementAlter.php

@@ -35,9 +35,12 @@ class ComponentElementAlter implements TrustedCallbackInterface {
   public function alter(array $element): array {
     $element = $this->normalizeSlots($element);
     $component = $this->componentPluginManager->find($element['#component']);
-    $element = $this->processAttributesProp($element, $component);
-    $element = $this->processAttributesRenderProperty($element);
     $element = $this->normalizeProps($element, $component);
+    // Attributes prop must never be empty, to avoid the processing of SDC's
+    // ComponentsTwigExtension::mergeAdditionalRenderContext() which is adding
+    // an Attribute PHP object before running the validator.
+    $element["#props"]["attributes"]['data-component-id'] = $component->getPluginId();
+    $element = $this->processAttributesRenderProperty($element);
     return $element;
   }
 
@@ -87,24 +90,6 @@ class ComponentElementAlter implements TrustedCallbackInterface {
     return $element;
   }
 
-  /**
-   * Process attributes prop.
-   */
-  public function processAttributesProp(array $element, Component $component): array {
-    $element["#props"]["attributes"] = $element["#props"]["attributes"] ?? [];
-    // Attribute PHP objects are rendered as strings by SDC ComponentValidator,
-    // this is raising an error: "InvalidComponentException: String value
-    // found, but an object is required".
-    if (is_a($element["#props"]["attributes"], '\Drupal\Core\Template\Attribute')) {
-      $element["#props"]["attributes"] = $element["#props"]["attributes"]->toArray();
-    }
-    // Attributes prop must never be empty, to avoid the processing of SDC's
-    // ComponentsTwigExtension::mergeAdditionalRenderContext() which is adding
-    // an Attribute PHP object.
-    $element["#props"]["attributes"]['data-component-id'] = $component->getPluginId();
-    return $element;
-  }
-
   /**
    * Process #attributes render property.
    *