Store info in plugin definition

Closes #3301754

src/Plugin/Action/FlagAction.php

@@ -66,8 +66,20 @@ class FlagAction extends ActionBase implements ContainerFactoryPluginInterface,
 
     parent::__construct($configuration, $plugin_id, $plugin_definition);
     $this->flagService = $flag_service;
-    $this->flag = $this->flagService->getFlagById($configuration['flag_id']);
-    $this->flagOperation = $configuration['flag_action'];
+    if ($configuration['flag_id']) {
+      $flag_id = $configuration['flag_id'];
+    }
+    else {
+      $flag_id = $plugin_definition['flag_id'];
+    }
+    if ($configuration['flag_action']) {
+      $flag_action = $configuration['flag_action'];
+    }
+    else {
+      $flag_action = $plugin_definition['flag_action'];
+    }
+    $this->flag = $this->flagService->getFlagById($flag_id);
+    $this->flagOperation = $flag_action;
   }
 
   /**