Issue #1978946 by tim-e: Convert comment_edit_page() to a Controller.

core/modules/comment/comment.module

@@ -247,11 +247,8 @@ function comment_menu() {
   // so we don't end up loading it twice (in the page and access callback).
   $items['comment/%comment/edit'] = array(
     'title' => 'Edit',
-    'page callback' => 'comment_edit_page',
-    'page arguments' => array(1),
-    'access callback' => 'entity_page_access',
-    'access arguments' => array(1, 'update'),
     'type' => MENU_LOCAL_TASK,
+    'route_name' => 'comment_edit_page',
   );
   $items['comment/%comment/approve'] = array(
     'title' => 'Approve',
@@ -1480,19 +1477,6 @@ function comment_get_display_page($cid, $node_type) {
   return floor($ordinal / $comments_per_page);
 }
 
-/**
- * Page callback: Displays the comment editing form.
- *
- * @param Drupal\comment\Comment $comment
- *   The comment object representing the comment to be edited.
- *
- * @see comment_menu()
- */
-function comment_edit_page(Comment $comment) {
-  drupal_set_title(t('Edit comment %comment', array('%comment' => $comment->subject->value)), PASS_THROUGH);
-  return entity_get_form($comment);
-}
-
 /**
  * Generates a comment preview.
  *

core/modules/comment/comment.routing.yml

@@ -0,0 +1,7 @@
+comment_edit_page:
+    pattern: 'comment/{comment}/edit'
+    defaults:
+        _entity_form: comment.default
+    requirements:
+        _entity_access: comment.update
+