ADS: Integrate newest base repository commits

* Update to newest version of ADS
* Remove native window and title bar support on linux

Base repository was merged until commit
8d4507e9d83434be976ff8c7bc9f59733937a08d

Task-number: QDS-10242
Change-Id: If74b6b50421be3b759c61b0f76f4a330991f71fa
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
Reviewed-by: Qt CI Patch Build Bot <ci_patchbuild_bot@qt.io>

src/libs/advanceddockingsystem/pushbutton.h

@@ -0,0 +1,47 @@
+// Copyright (C) 2020 Uwe Kindler
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-2.1-or-later OR GPL-3.0-or-later
+
+#pragma once
+
+#include "ads_globals.h"
+
+#include <QPushButton>
+
+namespace ADS {
+
+/**
+ * ADS specific push button class with orientation support
+ */
+class ADS_EXPORT PushButton : public QPushButton
+{
+    Q_OBJECT
+
+public:
+    enum Orientation {
+        Horizontal,
+        VerticalTopToBottom,
+        VerticalBottomToTop
+    };
+
+    using QPushButton::QPushButton;
+
+    virtual QSize sizeHint() const override;
+
+    /**
+     * Returns the current orientation
+     */
+    Orientation buttonOrientation() const;
+
+    /**
+     * Set the orientation of this button
+     */
+    void setButtonOrientation(Orientation orientation);
+
+protected:
+    virtual void paintEvent(QPaintEvent *event) override;
+
+private:
+    Orientation m_orientation = Horizontal;
+}; // class PushButton
+
+} // namespace ADS