Add NotificationAction.action member

Source/modules/notifications/Notification.cpp

Index: Source/modules/notifications/Notification.cpp
diff --git a/Source/modules/notifications/Notification.cpp b/Source/modules/notifications/Notification.cpp
index 6b73d6cfee3a64f03201bfc8e1020f79390b4960..8f8d0730f65877bca9914caf87688a03e1b61055 100644
--- a/Source/modules/notifications/Notification.cpp
+++ b/Source/modules/notifications/Notification.cpp
@@ -93,8 +93,12 @@ Notification* Notification::create(ExecutionContext* context, const String& titl
     }
 
     for (NotificationAction action : options.actions()) {
+        if (action.action().isEmpty()) {
+            exceptionState.throwTypeError("NotificationAction action must not be empty.");
+            return nullptr;
+        }
         if (action.title().isEmpty()) {
-            exceptionState.throwTypeError("Notification action titles must not be empty.");
+            exceptionState.throwTypeError("NotificationAction title must not be empty.");
             return nullptr;
         }
     }
@@ -309,6 +313,7 @@ void Notification::webActionsToActions(const WebVector<WebNotificationAction>& w
     actions.clear();
     actions.grow(webActions.size());
     for (size_t i = 0; i < webActions.size(); ++i) {
+        actions[i].setAction(webActions[i].action);
         actions[i].setTitle(webActions[i].title);
     }
 }