add missing file

Change-Id: I2dcbc2f299c8994cd11e24f0beffe491d8f4f278

vcl/unx/generic/gdi/x11windowprovider.cxx

+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include "unx/x11windowprovider.hxx"
+
+X11WindowProvider::~X11WindowProvider()
+{
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */