Issue #3105095 by mikeegoulding, Eric_A:...

Issue #3105095 by mikeegoulding, Eric_A: ElementInfoManagerInterface::getInfoProperty() return type incorrect

core/lib/Drupal/Core/Render/ElementInfoManagerInterface.php

@@ -57,7 +57,7 @@ public function getInfo($type);
    *   (Optional) The value to return if the element type does not specify a
    *   value for the property. Defaults to NULL.
    *
-   * @return string
+   * @return mixed
    *   The property value of the defined element type. Or the provided
    *   default value, which can be NULL.
    */