Implement the Notification `timestamp` property

content/browser/notifications/notification_database_data_conversions.cc

Index: content/browser/notifications/notification_database_data_conversions.cc
diff --git a/content/browser/notifications/notification_database_data_conversions.cc b/content/browser/notifications/notification_database_data_conversions.cc
index c6095e4055a17381bcbbe015bc00b4312fc06da0..a225c554c3dd9849cafae198b97db9803287995e 100644
--- a/content/browser/notifications/notification_database_data_conversions.cc
+++ b/content/browser/notifications/notification_database_data_conversions.cc
@@ -6,6 +6,7 @@
 
 #include "base/logging.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/time/time.h"
 #include "content/browser/notifications/notification_database_data.pb.h"
 #include "content/public/browser/notification_database_data.h"
 
@@ -55,6 +56,7 @@ bool DeserializeNotificationDatabaseData(const std::string& input,
         payload.vibration_pattern().end());
   }
 
+  notification_data->timestamp = base::Time::FromDoubleT(payload.timestamp());
   notification_data->silent = payload.silent();
   notification_data->require_interaction = payload.require_interaction();
 
@@ -107,6 +109,7 @@ bool SerializeNotificationDatabaseData(const NotificationDatabaseData& input,
   for (size_t i = 0; i < notification_data.vibration_pattern.size(); ++i)
     payload->add_vibration_pattern(notification_data.vibration_pattern[i]);
 
+  payload->set_timestamp(notification_data.timestamp.ToDoubleT());
   payload->set_silent(notification_data.silent);
   payload->set_require_interaction(notification_data.require_interaction);