Fixes the context menu for a notification.

chrome/browser/ui/views/message_center/web_notification_tray.cc

Index: chrome/browser/ui/views/message_center/web_notification_tray.cc
diff --git a/chrome/browser/ui/views/message_center/web_notification_tray.cc b/chrome/browser/ui/views/message_center/web_notification_tray.cc
index 7268b5d144c6430203caf727abc56ac9f471f59e..8cab3faddd05c7013c199b228514f77a0a5ba9c8 100644
--- a/chrome/browser/ui/views/message_center/web_notification_tray.cc
+++ b/chrome/browser/ui/views/message_center/web_notification_tray.cc
@@ -191,6 +191,12 @@ bool WebNotificationTray::ShowNotifierSettings() {
   return true;
 }
 
+bool WebNotificationTray::IsContextMenuEnabled() const {
+  // It can always return true because the notifications are invisible if
+  // the context menu shouldn't be enabled, such as in the lock screen.
+  return true;
+}
+
 void WebNotificationTray::OnMessageCenterTrayChanged() {
   if (status_icon_) {
     bool quiet_mode_state = message_center()->IsQuietMode();