3446876 - use own static cache to prevent static cache flushing during updates...

3446876 - use own static cache to prevent static cache flushing during updates to lose all collected data for config revisions

Closes #3446876

config_track.module

@@ -16,8 +16,7 @@ use Drupal\config_track\Controller\ConfigTrackController;
  */
 function config_track_entity_presave_first(EntityInterface $entity) {
  if ($entity instanceof ConfigEntityInterface) {
-   $config_track =& drupal_static('config_track', []);
-
+   $config_track =& config_track_static();
    // Only register the shutdown function once.
    if (empty($config_track)) {
      drupal_register_shutdown_function('config_track_shutdown');
@@ -39,7 +38,7 @@ function config_track_entity_presave_first(EntityInterface $entity) {
  */
 function config_track_entity_presave_last(EntityInterface $entity) {
   if ($entity instanceof ConfigEntityInterface) {
-    $config_track =& drupal_static('config_track', []);
+    $config_track =& config_track_static();
     $keys = array_keys($config_track);
     foreach (array_reverse($keys) as $key) {
       $config_data =& $config_track[$key];
@@ -69,7 +68,7 @@ function config_track_entity_presave_last(EntityInterface $entity) {
  */
 function config_track_entity_predelete_first(EntityInterface $entity) {
   if ($entity instanceof ConfigEntityInterface) {
-    $config_track =& drupal_static('config_track', []);
+    $config_track =& config_track_static();
 
     // Only register the shutdown function once.
     if (empty($config_track)) {
@@ -92,7 +91,7 @@ function config_track_entity_predelete_first(EntityInterface $entity) {
  */
 function config_track_entity_predelete_last(EntityInterface $entity) {
   if ($entity instanceof ConfigEntityInterface) {
-    $config_track =& drupal_static('config_track', []);
+    $config_track =& config_track_static();
     $keys = array_keys($config_track);
     foreach (array_reverse($keys) as $key) {
       $config_data =& $config_track[$key];
@@ -133,7 +132,7 @@ function config_track_shutdown() {
   }
 
   $timestamp = \Drupal::time()->getRequestTime();
-  $config_track =& drupal_static('config_track', []);
+  $config_track =& config_track_static();
   /** @var \Drupal\config_track\Controller\ConfigTrackController $config_track_controller */
   $config_track_controller = \Drupal::classResolver(ConfigTrackController::class);
   foreach ($config_track as $config_change) {
@@ -244,3 +243,16 @@ function config_track_convert_markup_to_string(array &$data) {
   }
   unset($value);
 }
+
+/**
+ * Returns a reference to the config_track static cache.
+ *
+ * @return array
+ */
+function &config_track_static() {
+  // We cannot use drupal_static() since drush updb clears the Drupal static
+  // caches before the shutdown functions are executed, however we need the
+  // static cache of config_track in the shutdown function.
+  static $config_track = [];
+  return $config_track;
+}