diff --git a/core/lib/Drupal/Core/Menu/Form/MenuLinkDefaultForm.php b/core/lib/Drupal/Core/Menu/Form/MenuLinkDefaultForm.php
index 964f5de..fa83457 100644
--- a/core/lib/Drupal/Core/Menu/Form/MenuLinkDefaultForm.php
+++ b/core/lib/Drupal/Core/Menu/Form/MenuLinkDefaultForm.php
@@ -109,8 +109,12 @@ public function buildConfigurationForm(array $form, array &$form_state) {
       '#type' => 'item',
       '#title' => $this->t('This link is provided by the @name module. The label and path cannot be edited.', array('@name' => $this->getModuleName($provider))),
     );
+    $link = array(
+      '#type' => 'link',
+      '#title' => $this->menuLink->getTitle(),
+    ) + $this->menuLink->getUrlObject()->toRenderArray();
     $form['path'] = array(
-      'link' => $this->menuLink->build(),
+      'link' => $link,
       '#type' => 'item',
       '#title' => $this->t('Link'),
     );
diff --git a/core/lib/Drupal/Core/Menu/MenuLinkBase.php b/core/lib/Drupal/Core/Menu/MenuLinkBase.php
index 7ad3de5..031b272 100644
--- a/core/lib/Drupal/Core/Menu/MenuLinkBase.php
+++ b/core/lib/Drupal/Core/Menu/MenuLinkBase.php
@@ -24,25 +24,6 @@
   protected $overrideAllowed = array();
 
   /**
-   * {@inheritdoc}
-   */
-  public function build($title_attribute = TRUE) {
-    $options = $this->getOptions();
-    $description = $this->getDescription();
-    if ($title_attribute && $description) {
-      $options['attributes']['title'] = $description;
-    }
-    $build = array(
-      '#type' => 'link',
-      '#route_name' => $this->pluginDefinition['route_name'],
-      '#route_parameters' => $this->pluginDefinition['route_parameters'],
-      '#title' => $this->getTitle(),
-      '#options' => $options,
-    );
-    return $build;
-  }
-
-  /**
    * Returns the weight of the menu link.
    *
    * @return int
diff --git a/core/lib/Drupal/Core/Menu/MenuLinkInterface.php b/core/lib/Drupal/Core/Menu/MenuLinkInterface.php
index 169a0a5..36d8520 100644
--- a/core/lib/Drupal/Core/Menu/MenuLinkInterface.php
+++ b/core/lib/Drupal/Core/Menu/MenuLinkInterface.php
@@ -16,17 +16,6 @@
 interface MenuLinkInterface extends PluginInspectionInterface, DerivativeInspectionInterface {
 
   /**
-   * Return a localized link render array.
-   *
-   * @param bool $title_attribute
-   *   If TRUE, add the link description (if present) as the title attribute.
-   *
-   * @return array
-   *   A render array with localized or translated strings.
-   */
-  public function build($title_attribute = TRUE);
-
-  /**
    * Returns the weight of the menu link.
    *
    * @return int
diff --git a/core/lib/Drupal/Core/Menu/MenuLinkTree.php b/core/lib/Drupal/Core/Menu/MenuLinkTree.php
index baaac0c..a0f3416 100644
--- a/core/lib/Drupal/Core/Menu/MenuLinkTree.php
+++ b/core/lib/Drupal/Core/Menu/MenuLinkTree.php
@@ -82,11 +82,11 @@ public function getCurrentRouteMenuTreeParameters($menu_name) {
     $parameters = new MenuTreeParameters();
     $parameters->setActiveTrail($active_trail)
       // We want links in the active trail to be expanded.
-      ->addExpanded($active_trail)
+      ->addExpandedParents($active_trail)
       // We marked the links in the active trail to be expanded, but we also
       // want their descendants that have the "expanded" flag enabled to be
       // expanded.
-      ->addExpanded($this->treeStorage->getExpanded($menu_name, $active_trail));
+      ->addExpandedParents($this->treeStorage->getExpanded($menu_name, $active_trail));
 
     return $parameters;
   }
@@ -218,4 +218,11 @@ public function getSubtreeHeight($id) {
     return $this->treeStorage->getSubtreeHeight($id);
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getExpanded($menu_name, array $parents) {
+    return $this->treeStorage->getExpanded($menu_name, $parents);
+  }
+
 }
diff --git a/core/lib/Drupal/Core/Menu/MenuLinkTreeInterface.php b/core/lib/Drupal/Core/Menu/MenuLinkTreeInterface.php
index df983fe..9b1f5df 100644
--- a/core/lib/Drupal/Core/Menu/MenuLinkTreeInterface.php
+++ b/core/lib/Drupal/Core/Menu/MenuLinkTreeInterface.php
@@ -126,4 +126,17 @@ public function maxDepth();
    */
   public function getSubtreeHeight($id);
 
+  /**
+   * Find expanded links in a menu given a set of possible parents.
+   *
+   * @param string $menu_name
+   *   The menu name.
+   * @param array $parents
+   *   One or more parent IDs to match.
+   *
+   * @return array
+   *   The menu link IDs that are flagged as expanded in this menu.
+   */
+  public function getExpanded($menu_name, array $parents);
+
 }
diff --git a/core/lib/Drupal/Core/Menu/MenuTreeParameters.php b/core/lib/Drupal/Core/Menu/MenuTreeParameters.php
index 4976598..d8adb40 100644
--- a/core/lib/Drupal/Core/Menu/MenuTreeParameters.php
+++ b/core/lib/Drupal/Core/Menu/MenuTreeParameters.php
@@ -13,8 +13,8 @@
  * Menu tree parameters are used to determine the set of definitions to be
  * loaded from \Drupal\Core\Menu\MenuTreeStorageInterface. Hence they determine
  * the shape and content of the tree:
- * - which links should be expanded, i.e. subtrees will get loaded that may not
- *   be loaded otherwise
+ * - which parent IDs should be used to restrict the tree, i.e. only links with
+ *   a parent in the list will be included.
  * - which menu links are omitted, i.e. minimum and maximum depth
  *
  * @todo - add getter methods and make all properties protected.
@@ -51,19 +51,19 @@ class MenuTreeParameters {
   public $maxDepth = NULL;
 
   /**
-   * An array of parent link ids to return only menu links that are children of
-   * one of the menu link plugin IDs in this list. If empty, the whole menu tree
-   * is built.
-   *
-   * Defaults to the empty array.
+   * An array of parent link IDs. This restricts the tree to only menu links
+   * that are at the top level or have a parent ID in this list. If empty, the
+   * whole menu tree is built.
    *
    * @var string[]
    */
-  public $expanded = array();
+  public $expandedParents = array();
 
   /**
    * An array of menu link plugin IDs, representing the trail from the currently
-   * active menu link to the ("real") root of that menu link's menu.
+   * active menu link to the ("real") root of that menu link's menu.  This does
+   * not affect the way the tree is built, it only is used to set the value of
+   * the inActiveTrail property for each tree element.
    *
    * Defaults to the empty array.
    *
@@ -125,22 +125,21 @@ public function setMaxDepth($max_depth) {
   }
 
   /**
-   * Adds menu links to be expanded (whose children to show).
+   * Adds parent menu links IDs to restrict the tree (only show children).
    *
-   * @param string[] $expanded
-   *   An array containing the links to be expanded: a list of menu link plugin
-   *   IDs.
+   * @param string[] $parents
+   *   An array containing the parent IDs to limit the tree.
    *
    * @return $this
    */
-  public function addExpanded(array $expanded) {
-    $this->expanded = array_merge($this->expanded, $expanded);
-    $this->expanded = array_unique($this->expanded);
+  public function addExpandedParents(array $parents) {
+    $this->expandedParents = array_merge($this->expandedParents, $parents);
+    $this->expandedParents = array_unique($this->expandedParents);
     return $this;
   }
 
   /**
-   * Sets the active trail.
+   * Sets the active trail IDs used to set the inActiveTrail property.
    *
    * @param string[] $active_trail
    *   An array containing the active trail: a list of menu link plugin IDs.
diff --git a/core/lib/Drupal/Core/Menu/MenuTreeStorage.php b/core/lib/Drupal/Core/Menu/MenuTreeStorage.php
index 5367622..89e0c80 100644
--- a/core/lib/Drupal/Core/Menu/MenuTreeStorage.php
+++ b/core/lib/Drupal/Core/Menu/MenuTreeStorage.php
@@ -766,7 +766,7 @@ protected function saveRecursive($id, &$children, &$links) {
   public function loadTreeData($menu_name, MenuTreeParameters $parameters) {
     // Build the cache id; sort 'expanded' and 'conditions' to prevent duplicate
     // cache items.
-    sort($parameters->expanded);
+    sort($parameters->expandedParents);
     sort($parameters->conditions);
     // @todo - may be able to skip hashing after https://drupal.org/node/2224847
     $tree_cid = "tree-data:$menu_name:" . hash('sha256', serialize($parameters));
@@ -862,8 +862,8 @@ protected function loadLinks($menu_name, MenuTreeParameters $parameters) {
 
     $query->condition('menu_name', $menu_name);
 
-    if (!empty($parameters->expanded)) {
-      $query->condition('parent', $parameters->expanded, 'IN');
+    if (!empty($parameters->expandedParents)) {
+      $query->condition('parent', $parameters->expandedParents, 'IN');
     }
     if (isset($parameters->minDepth) && $parameters->minDepth > 1) {
       $query->condition('depth', $parameters->minDepth, '>=');
diff --git a/core/tests/Drupal/Tests/Core/Menu/MenuLinkTreeParametersTest.php b/core/tests/Drupal/Tests/Core/Menu/MenuLinkTreeParametersTest.php
index e4da62d..f0118db 100644
--- a/core/tests/Drupal/Tests/Core/Menu/MenuLinkTreeParametersTest.php
+++ b/core/tests/Drupal/Tests/Core/Menu/MenuLinkTreeParametersTest.php
@@ -68,29 +68,29 @@ public function testSetMinDepth($min_depth, $expected) {
   }
 
   /**
-   * Tests addExpanded().
+   * Tests addExpandedParents().
    *
-   * @covers ::addExpanded
+   * @covers ::addExpandedParents
    */
   public function testAddExpanded() {
     $parameters = new MenuTreeParameters();
 
     // Verify default value.
-    $this->assertEquals(array(), $parameters->expanded);
+    $this->assertEquals(array(), $parameters->expandedParents);
 
     // Add actual menu link plugin IDs to be expanded.
-    $parameters->addExpanded(array('foo', 'bar', 'baz'));
-    $this->assertEquals(array('foo', 'bar', 'baz'), $parameters->expanded);
+    $parameters->addExpandedParents(array('foo', 'bar', 'baz'));
+    $this->assertEquals(array('foo', 'bar', 'baz'), $parameters->expandedParents);
 
     // Add additional menu link plugin IDs; they should be merged, not replacing
     // the old ones.
-    $parameters->addExpanded(array('qux', 'quux'));
-    $this->assertEquals(array('foo', 'bar', 'baz', 'qux', 'quux'), $parameters->expanded);
+    $parameters->addExpandedParents(array('qux', 'quux'));
+    $this->assertEquals(array('foo', 'bar', 'baz', 'qux', 'quux'), $parameters->expandedParents);
 
     // Add pre-existing menu link plugin IDs; they should not be added again;
     // this is a set.
-    $parameters->addExpanded(array('bar', 'quux'));
-    $this->assertEquals(array('foo', 'bar', 'baz', 'qux', 'quux'), $parameters->expanded);
+    $parameters->addExpandedParents(array('bar', 'quux'));
+    $this->assertEquals(array('foo', 'bar', 'baz', 'qux', 'quux'), $parameters->expandedParents);
   }
 
   /**