updated core to 7.53

includes/database/sqlite/database.inc

@@ -378,6 +378,14 @@ class DatabaseConnection_sqlite extends DatabaseConnection {
     }
   }
 
+  public function utf8mb4IsActive() {
+    return TRUE;
+  }
+
+  public function utf8mb4IsSupported() {
+    return TRUE;
+  }
+
 }
 
 /**

includes/database/sqlite/install.inc

@@ -14,8 +14,6 @@ class DatabaseTasks_sqlite extends DatabaseTasks {
 
   /**
    * Minimum engine version.
-   *
-   * @todo: consider upping to 3.6.8 in Drupal 8 to get SAVEPOINT support.
    */
   public function minimumVersion() {
     return '3.3.7';