Issue #1798760 by ACF, alexpott: Convert menu_masks() to the state system.

core/includes/menu.inc

@@ -319,10 +319,10 @@ function menu_get_ancestors($parts) {
   $ancestors = array();
   $length =  $number_parts - 1;
   $end = (1 << $number_parts) - 1;
-  $masks = variable_get('menu_masks');
-  // If the optimized menu_masks array is not available use brute force to get
+  $masks = state()->get('menu.masks');
+  // If the optimized menu.masks array is not available use brute force to get
   // the correct $ancestors and $placeholders returned. Do not use this as the
-  // default value of the menu_masks variable to avoid building such a big
+  // default value of the menu.masks variable to avoid building such a big
   // array.
   if (!$masks) {
     $masks = range(511, 1);
@@ -453,7 +453,7 @@ function menu_get_item($path = NULL, $router_item = NULL) {
   if (!isset($router_items[$path])) {
     // Rebuild if we know it's needed, or if the menu masks are missing which
     // occurs rarely, likely due to a race condition of multiple rebuilds.
-    if (state()->get('menu_rebuild_needed') || !variable_get('menu_masks', array())) {
+    if (state()->get('menu_rebuild_needed') || !state()->get('menu.masks')) {
       menu_router_rebuild();
     }
     $original_map = arg(NULL, $path);
@@ -3784,7 +3784,7 @@ function _menu_router_save($menu, $masks) {
   // Insert any remaining records.
   $insert->execute();
   // Store the masks.
-  variable_set('menu_masks', $masks);
+  state()->set('menu.masks', $masks);
 
   return $menu;
 }

core/modules/system/lib/Drupal/system/Tests/Menu/RouterTest.php

@@ -423,7 +423,7 @@ function testMenuHidden() {
    * Test menu_get_item() with empty ancestors.
    */
   function testMenuGetItemNoAncestors() {
-    variable_set('menu_masks', array());
+    state()->set('menu.masks', array());
     $this->drupalGet('');
   }
 

core/modules/system/system.install

@@ -2154,6 +2154,14 @@ function system_update_8027() {
   update_variable_del('javascript_parsed');
 }
 
+/**
+ * Remove the 'menu_masks' configuration variable.
+ */
+function system_update_8028() {
+  // No upgrade path needed since the menu router will be rebuilt during d7 to d8 upgrade.
+  update_variable_del('menu_masks');
+}
+
 /**
  * @} End of "defgroup updates-7.x-to-8.x".
  * The next series of updates should start at 9000.