diff --git a/core/includes/menu.inc b/core/includes/menu.inc
index 0ca3b65..17c65c1 100644
--- a/core/includes/menu.inc
+++ b/core/includes/menu.inc
@@ -153,8 +153,8 @@
  * - weight: Lower (negative) numbers come before higher (positive) numbers,
  *   for menu items with the same parent.
  *
- * Menu items from other modules can be altered using
- * hook_menu_link_defaults_alter().
+ * Discovered menu links from other modules can be altered using
+ * hook_menu_links_discovered_alter().
  *
  * @todo Derivatives will probably be defined for these; when they are, add
  *   documentation here.
diff --git a/core/lib/Drupal/Core/EventSubscriber/MenuRouterRebuildSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/MenuRouterRebuildSubscriber.php
index ba2cc7b..4b0b41f 100644
--- a/core/lib/Drupal/Core/EventSubscriber/MenuRouterRebuildSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/MenuRouterRebuildSubscriber.php
@@ -30,7 +30,7 @@ class MenuRouterRebuildSubscriber implements EventSubscriberInterface {
   protected $lock;
 
   /**
-   * The menu link plugin manager
+   * The menu link plugin manager.
    *
    * @var \Drupal\Core\Menu\MenuLinkManagerInterface $menuLinkManager
    */
@@ -96,4 +96,3 @@ static function getSubscribedEvents() {
   }
 
 }
-
diff --git a/core/lib/Drupal/Core/EventSubscriber/RouterRebuildSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/RouterRebuildSubscriber.php
index 69f49e4..584b141 100644
--- a/core/lib/Drupal/Core/EventSubscriber/RouterRebuildSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/RouterRebuildSubscriber.php
@@ -11,7 +11,6 @@
 use Drupal\Core\Lock\LockBackendInterface;
 use Drupal\Core\Routing\RouteBuilderInterface;
 use Drupal\Core\Routing\RoutingEvents;
-use Drupal\Core\Menu\MenuLinkManagerInterface;
 use Symfony\Component\EventDispatcher\Event;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 use Symfony\Component\HttpKernel\Event\PostResponseEvent;
diff --git a/core/lib/Drupal/Core/Menu/MenuLinkBase.php b/core/lib/Drupal/Core/Menu/MenuLinkBase.php
index 43cb49a..331b26b 100644
--- a/core/lib/Drupal/Core/Menu/MenuLinkBase.php
+++ b/core/lib/Drupal/Core/Menu/MenuLinkBase.php
@@ -40,18 +40,7 @@ public function getWeight() {
   /**
    * {@inheritdoc}
    */
-  public function getTitle() {
-    // Subclasses may pull in the request or specific attributes as parameters.
-    $options = array();
-    if (!empty($this->pluginDefinition['title_context'])) {
-      $options['context'] = $this->pluginDefinition['title_context'];
-    }
-    $args = array();
-    if (isset($this->pluginDefinition['title_arguments']) && $title_arguments = $this->pluginDefinition['title_arguments']) {
-      $args = (array) $title_arguments;
-    }
-    return $this->t($this->pluginDefinition['title'], $args, $options);
-  }
+  abstract public function getTitle();
 
   /**
    * {@inheritdoc}
@@ -112,12 +101,7 @@ public function isDeletable() {
   /**
    * {@inheritdoc}
    */
-  public function getDescription() {
-    if ($this->pluginDefinition['description']) {
-      return $this->t($this->pluginDefinition['description']);
-    }
-    return '';
-  }
+  abstract public function getDescription();
 
   /**
    * {@inheritdoc}
@@ -190,6 +174,11 @@ public function getTranslateRoute() {
   /**
    * {@inheritdoc}
    */
+  abstract public function updateLink(array $new_definition_values, $persist);
+
+  /**
+   * {@inheritdoc}
+   */
   public function deleteLink() {
     throw new PluginException(String::format('Menu link plugin with ID @id does not support deletion', array('@id' => $this->getPluginId())));
   }
diff --git a/core/lib/Drupal/Core/Menu/MenuLinkDefault.php b/core/lib/Drupal/Core/Menu/MenuLinkDefault.php
index f84e0b2..5d0f8e2 100644
--- a/core/lib/Drupal/Core/Menu/MenuLinkDefault.php
+++ b/core/lib/Drupal/Core/Menu/MenuLinkDefault.php
@@ -66,6 +66,32 @@ public static function create(ContainerInterface $container, array $configuratio
   /**
    * {@inheritdoc}
    */
+  public function getTitle() {
+    // Subclasses may pull in the request or specific attributes as parameters.
+    $options = array();
+    if (!empty($this->pluginDefinition['title_context'])) {
+      $options['context'] = $this->pluginDefinition['title_context'];
+    }
+    $args = array();
+    if (isset($this->pluginDefinition['title_arguments']) && $title_arguments = $this->pluginDefinition['title_arguments']) {
+      $args = (array) $title_arguments;
+    }
+    return $this->t($this->pluginDefinition['title'], $args, $options);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getDescription() {
+    if ($this->pluginDefinition['description']) {
+      return $this->t($this->pluginDefinition['description']);
+    }
+    return '';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function isResettable() {
     // The link can be reset if it has an override.
     return (bool) $this->staticOverride->loadOverride($this->getPluginId());
diff --git a/core/lib/Drupal/Core/Menu/MenuLinkTree.php b/core/lib/Drupal/Core/Menu/MenuLinkTree.php
index 943698c..e5d54fe 100644
--- a/core/lib/Drupal/Core/Menu/MenuLinkTree.php
+++ b/core/lib/Drupal/Core/Menu/MenuLinkTree.php
@@ -63,7 +63,8 @@ class MenuLinkTree implements MenuLinkTreeInterface {
   /**
    * Stores the cached current route parameters by menu and current route match.
    *
-   * @todo Remove this non-static caching in https://www.drupal.org/node/1805054.
+   * @todo Remove this non-static caching in
+   *   https://www.drupal.org/node/1805054.
    *
    * @var \Drupal\Core\Menu\MenuTreeParameters[]
    */
diff --git a/core/lib/Drupal/Core/Utility/LinkGenerator.php b/core/lib/Drupal/Core/Utility/LinkGenerator.php
index 54a2635..d3093ac 100644
--- a/core/lib/Drupal/Core/Utility/LinkGenerator.php
+++ b/core/lib/Drupal/Core/Utility/LinkGenerator.php
@@ -101,7 +101,7 @@ public function generateFromUrl($text, Url $url) {
         // @todo System path is deprecated - use the route name and parameters.
         $system_path = $url->getInternalPath();
         // Special case for the front page.
-        $variables['options']['attributes']['data-drupal-link-system-path'] = $system_path != '' ?: '<front>';
+        $variables['options']['attributes']['data-drupal-link-system-path'] = $system_path == '' ? '<front>' : $system_path;
       }
     }
 
diff --git a/core/modules/menu_ui/src/MenuForm.php b/core/modules/menu_ui/src/MenuForm.php
index 658986c..91000b5 100644
--- a/core/modules/menu_ui/src/MenuForm.php
+++ b/core/modules/menu_ui/src/MenuForm.php
@@ -249,7 +249,7 @@ protected function buildOverviewForm(array &$form, array &$form_state) {
    * Recursive helper function for buildOverviewForm().
    *
    * @param $tree
-   *   The menu_tree retrieved by menu_tree_data.
+   *   The tree retrieved by \Drupal\Core\Menu\MenuLinkTreeInterface::load().
    * @param $delta
    *   The default number of menu items used in the menu weight selector is 50.
    *
diff --git a/core/modules/system/src/Tests/Menu/MenuRouterTest.php b/core/modules/system/src/Tests/Menu/MenuRouterTest.php
index 406c134..270badc 100644
--- a/core/modules/system/src/Tests/Menu/MenuRouterTest.php
+++ b/core/modules/system/src/Tests/Menu/MenuRouterTest.php
@@ -52,7 +52,7 @@ public function testMenuIntegration() {
     $this->doTestMenuOptionalPlaceholders();
     $this->doTestMenuOnRoute();
     $this->doTestMenuName();
-    $this->doTestMenuLinkDefaultsAlter();
+    $this->doTestMenuLinksDiscoveredAlter();
     $this->doTestHookMenuIntegration();
     $this->doTestExoticPath();
   }
@@ -127,21 +127,21 @@ protected function doTestMenuName() {
   }
 
   /**
-   * Tests menu links added in hook_menu_link_defaults_alter().
+   * Tests menu links added in hook_menu_links_discovered_alter().
    */
-  protected function doTestMenuLinkDefaultsAlter() {
+  protected function doTestMenuLinksDiscoveredAlter() {
     // Check that machine name does not need to be defined since it is already
     // set as the key of each menu link.
     /** @var \Drupal\Core\Menu\MenuLinkManagerInterface $menu_link_manager */
     $menu_link_manager = \Drupal::service('plugin.manager.menu.link');
     $menu_links = $menu_link_manager->loadLinksByRoute('menu_test.custom');
     $menu_link = reset($menu_links);
-    $this->assertEqual($menu_link->getPluginId(), 'menu_test.custom', 'Menu links added at hook_menu_link_defaults_alter() obtain the machine name from the $links key.');
+    $this->assertEqual($menu_link->getPluginId(), 'menu_test.custom', 'Menu links added at hook_menu_links_discovered_alter() obtain the machine name from the $links key.');
     // Make sure that rebuilding the menu tree does not produce duplicates of
-    // links added by hook_menu_link_defaults_alter().
+    // links added by hook_menu_links_discovered_alter().
     \Drupal::service('router.builder')->rebuild();
     $this->drupalGet('menu-test');
-    $this->assertUniqueText('Custom link', 'Menu links added by hook_menu_link_defaults_alter() do not duplicate after a menu rebuild.');
+    $this->assertUniqueText('Custom link', 'Menu links added by hook_menu_links_discovered_alter() do not duplicate after a menu rebuild.');
   }
 
   /**
diff --git a/core/modules/views/src/Plugin/Derivative/ViewsMenuLink.php b/core/modules/views/src/Plugin/Derivative/ViewsMenuLink.php
index da5007a..e83af2b 100644
--- a/core/modules/views/src/Plugin/Derivative/ViewsMenuLink.php
+++ b/core/modules/views/src/Plugin/Derivative/ViewsMenuLink.php
@@ -34,7 +34,8 @@ public function getDerivativeDefinition($derivative_id, $base_plugin_definition)
    */
   public function getDerivativeDefinitions($base_plugin_definition) {
     $links = array();
-    // @todo Replaces uses_hook_menu with a different annotation.
+    // @todo Replace uses_hook_menu with an annotation.
+    //   https://www.drupal.org/node/2310371
     $views = Views::getApplicableViews('uses_hook_menu');
     foreach ($views as $data) {
       /** @var \Drupal\views\ViewExecutable $view */
diff --git a/core/modules/views/src/Plugin/Menu/Form/ViewsMenuLinkForm.php b/core/modules/views/src/Plugin/Menu/Form/ViewsMenuLinkForm.php
index db8b691..d97b204 100644
--- a/core/modules/views/src/Plugin/Menu/Form/ViewsMenuLinkForm.php
+++ b/core/modules/views/src/Plugin/Menu/Form/ViewsMenuLinkForm.php
@@ -12,8 +12,8 @@
 /**
  * Provides a form to edit Views menu links.
  *
- * This provides the feature to edit the title, in contrast to the static
- * menu link form.
+ * This provides the feature to edit the title and description, in contrast to
+ * the default menu link form.
  *
  * @see \Drupal\views\Plugin\Menu\ViewsMenuLink
  */
@@ -35,7 +35,8 @@ public function buildConfigurationForm(array $form, array &$form_state) {
     $form['title'] = array(
       '#type' => 'textfield',
       '#title' => $this->t('Title'),
-      // @todo how do we ensure that view is not loaded with a translation?
+      // @todo Ensure that the view is not loaded with a localized title.
+      //   https://www.drupal.org/node/2309507
       '#default_value' => $this->menuLink->getTitle(),
       '#weight' => -10,
     );
@@ -44,9 +45,9 @@ public function buildConfigurationForm(array $form, array &$form_state) {
       '#type' => 'textfield',
       '#title' => $this->t('Description'),
       '#description' => $this->t('Shown when hovering over the menu link.'),
-      // @todo how do we ensure that view is not loaded with a translation,
-      //   see https://www.drupal.org/node/2309507
-      '#default_value' => $this->menuLink->getTitle(),
+      // @todo Ensure that the view is not loaded with a localized description.
+      //   https://www.drupal.org/node/2309507
+      '#default_value' => $this->menuLink->getDescription(),
       '#weight' => -5,
     );
 
diff --git a/core/modules/views/src/Plugin/Menu/ViewsMenuLink.php b/core/modules/views/src/Plugin/Menu/ViewsMenuLink.php
index b7944a6..ff47b54 100644
--- a/core/modules/views/src/Plugin/Menu/ViewsMenuLink.php
+++ b/core/modules/views/src/Plugin/Menu/ViewsMenuLink.php
@@ -115,8 +115,8 @@ public function loadView() {
    * {@inheritdoc}
    */
   public function getTitle() {
-    // @todo - can we get the translated value from the config without
-    // instantiating the view?
+    // @todo Get the translated value from the config without instantiating the
+    //   view. https://www.drupal.org/node/2310379
     return $this->loadView()->display_handler->getOption('menu')['title'];
   }
 
@@ -144,8 +144,8 @@ public function updateLink(array $new_definition_values, $persist) {
         }
       }
       if ($changed) {
-        // @todo Note: This triggers a full rebuild of everything, even we just
-        //   changed some properties..
+        // @todo Improve this to not trigger a full rebuild of everything, if we
+        //   just changed some properties. https://www.drupal.org/node/2310389
         $view->storage->save();
       }
     }
diff --git a/core/tests/Drupal/Tests/Core/Menu/MenuLinkMock.php b/core/tests/Drupal/Tests/Core/Menu/MenuLinkMock.php
index 7086aa6..9a9e98e 100644
--- a/core/tests/Drupal/Tests/Core/Menu/MenuLinkMock.php
+++ b/core/tests/Drupal/Tests/Core/Menu/MenuLinkMock.php
@@ -28,7 +28,6 @@ class MenuLinkMock extends MenuLinkBase {
     'options' => array(),
     'expanded' => '0',
     'hidden' => '0',
-    'discovered' => '1',
     'provider' => 'simpletest',
     'metadata' => array(),
     'class' => 'Drupal\\Tests\\Core\Menu\\MenuLinkMock',