diff -u b/core/modules/user/lib/Drupal/user/ProfileFormController.php b/core/modules/user/lib/Drupal/user/ProfileFormController.php
--- b/core/modules/user/lib/Drupal/user/ProfileFormController.php
+++ b/core/modules/user/lib/Drupal/user/ProfileFormController.php
@@ -7,22 +7,37 @@
 
 namespace Drupal\user;
 
+use Symfony\Component\HttpFoundation\Request;
+
 /**
  * Form controller for the profile forms.
  */
 class ProfileFormController extends AccountFormController {
 
+   /**
+    * {@inheritdoc}
+    */
+  public function buildForm(array $form, array &$form_state, Request $request = NULL) {
+    $this->request = $request;
+    return parent::buildForm($form, $form_state);
+  }
+
   /**
    * Overrides Drupal\Core\Entity\EntityFormController::actions().
    */
   protected function actions(array $form, array &$form_state) {
     $element = parent::actions($form, $form_state);
+
+    // The user account being edited.
     $account = $this->entity;
 
+    // The user doing the editing.
+    $user = $this->request->attributes->get('_account');
+
     $element['delete']['#type'] = 'submit';
     $element['delete']['#value'] = t('Cancel account');
     $element['delete']['#submit'] = array(array($this, 'editCancelSubmit'));
-    $element['delete']['#access'] = $account->id() > 1 && (($account->id() == $GLOBALS['user']->id() && user_access('cancel account')) || user_access('administer users'));
+    $element['delete']['#access'] = $account->id() > 1 && (($account->id() == $user->id() && $user->hasPermission('cancel account')) || $user->hasPermission('administer users'));
 
     return $element;
   }
@@ -44,16 +59,16 @@
 
   /**
-   * Submit method for the 'Cancel account' button.
+   * Provides a submit handler for the 'Cancel account' button.
    */
   public function editCancelSubmit($form, &$form_state) {
     $destination = array();
-    $query = Drupal::request()->query;
+    $query = $this->request->query;
     if ($query->has('destination')) {
-      $destination = drupal_get_destination();
+      $destination = array('destination' => $query->get('destination'));
       $query->remove('destination');
     }
     // Note: We redirect from user/uid/edit to user/uid/cancel to make the tabs disappear.
-    $account = $form_state['controller']->getEntity();
-    $form_state['redirect'] = array("user/" . $account->id() . "/cancel", array('query' => $destination));
+    $account = $form_state['controller']->entity;
+    $form_state['redirect'] = array('user/' . $account->id() . '/cancel', array('query' => $destination));
   }
 }
only in patch2:
unchanged:
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermTest.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermTest.php
@@ -348,11 +348,6 @@ function testTermInterface() {
     // Check that the term feed page is working.
     $this->drupalGet('taxonomy/term/' . $term->id() . '/feed');
 
-    // Check that the term edit page does not try to interpret additional path
-    // components as arguments for entity_get_form().
-    $this->drupalGet('taxonomy/term/' . $term->id() . '/edit/' . $this->randomName());
-    $this->assertResponse(200, 'The taxonomy term edit menu item ensured appropriate arguments were passed to its page callback.');
-
     // Delete the term.
     $this->drupalPost('taxonomy/term/' . $term->id() . '/edit', array(), t('Delete'));
     $this->drupalPost(NULL, NULL, t('Delete'));