diff --git a/core/lib/Drupal/Core/Config/Schema/Mapping.php b/core/lib/Drupal/Core/Config/Schema/Mapping.php
index 5729390..a626b92 100644
--- a/core/lib/Drupal/Core/Config/Schema/Mapping.php
+++ b/core/lib/Drupal/Core/Config/Schema/Mapping.php
@@ -46,6 +46,10 @@ protected function parse() {
    *
    * Since all configuration objects are mappings the function will except a dot
    * delimited key to access nested values, for example, 'page.front'.
+   *
+   * @throws \Drupal\Core\Config\Schema\SchemaIncompleteException
+   *   If a property is requested that does not have schema or does not exist in
+   *   the data.
    */
   public function get($property_name) {
     $parts = explode('.', $property_name);
@@ -55,14 +59,14 @@ public function get($property_name) {
       $element = $elements[$root_key];
     }
     else {
-      throw new SchemaIncompleteException(String::format("The configuration property @key doesn't exist.", array('@key' => $property_name)));
+      throw new SchemaIncompleteException(String::format("@key.@element does not exist or does not have schema defined.", array('@key' => $this->getFullName(), '@element' => $property_name)));
     }
 
     // If $property_name contained a dot recurse into the keys.
     foreach ($parts as $key) {
      if (!is_object($element) || !method_exists($element, 'get')) {
-        throw new SchemaIncompleteException(String::format("The configuration property @key does not exist.", array('@key' => $property_name)));
-      }
+       throw new SchemaIncompleteException(String::format("@key.@element does not exist or does not have schema defined.", array('@key' => $this->getFullName(), '@element' => $property_name)));
+     }
       $element = $element->get($key);
     }
     return $element;
diff --git a/core/lib/Drupal/Core/Config/Schema/SchemaCheckTrait.php b/core/lib/Drupal/Core/Config/Schema/SchemaCheckTrait.php
index 4348316..893fc6c 100644
--- a/core/lib/Drupal/Core/Config/Schema/SchemaCheckTrait.php
+++ b/core/lib/Drupal/Core/Config/Schema/SchemaCheckTrait.php
@@ -54,7 +54,7 @@ public function checkConfigSchema(TypedConfigManagerInterface $typed_config, $co
     }
     $definition = $typed_config->getDefinition($config_name);
     $data_definition = $typed_config->buildDataDefinition($definition, $config_data);
-    $this->schema = $typed_config->create($data_definition, $config_data);
+    $this->schema = $typed_config->create($data_definition, $config_data, $config_name);
     $errors = array();
     foreach ($config_data as $key => $value) {
       $errors = array_merge($errors, $this->checkValue($key, $value));
diff --git a/core/lib/Drupal/Core/Config/StorableConfigBase.php b/core/lib/Drupal/Core/Config/StorableConfigBase.php
index b2610f7..f40c4a6 100644
--- a/core/lib/Drupal/Core/Config/StorableConfigBase.php
+++ b/core/lib/Drupal/Core/Config/StorableConfigBase.php
@@ -170,16 +170,7 @@ protected function validateValue($key, $value) {
    *   Exception on unsupported/undefined data type deducted.
    */
   protected function castValue($key, $value) {
-    $element = FALSE;
-    try {
-      $element = $this->getSchemaWrapper()->get($key);
-    }
-    catch (SchemaIncompleteException $e) {
-      // @todo Consider making schema handling more strict by throwing
-      // SchemaIncompleteException for all incomplete schema conditions *and*
-      // throwing it forward. See https://drupal.org/node/2183983.
-      // Until then, we need to handle the Undefined case below.
-    }
+    $element = $this->getSchemaWrapper()->get($key);
     // Do not cast value if it is unknown or defined to be ignored.
     if ($element && ($element instanceof Undefined || $element instanceof Ignore)) {
       return $value;
diff --git a/core/modules/menu_ui/config/schema/menu_ui.schema.yml b/core/modules/menu_ui/config/schema/menu_ui.schema.yml
index ce6be8b..7625f0d 100644
--- a/core/modules/menu_ui/config/schema/menu_ui.schema.yml
+++ b/core/modules/menu_ui/config/schema/menu_ui.schema.yml
@@ -24,3 +24,6 @@ menu.entity.node.*:
       sequence:
        - type: string
          label: 'Menu machine name'
+    parent:
+      type: string
+      label: 'Parent'