Disable tooltips through event filter (#6192)

* Control tooltip visibility using an event filter

...removing the need for a ToolTip helper class

* Remove whitespace

include/MainWindow.h

@@ -135,6 +135,8 @@ public:
 	static void saveWidgetState( QWidget * _w, QDomElement & _de );
 	static void restoreWidgetState( QWidget * _w, const QDomElement & _de );
 
+	bool eventFilter(QObject* watched, QEvent* event) override;
+
 public slots:
 	void resetWindowTitle();
 

include/MixerView.h

@@ -34,7 +34,6 @@
 #include "Engine.h"
 #include "Fader.h"
 #include "PixmapButton.h"
-#include "ToolTip.h"
 #include "embed.h"
 #include "EffectRackView.h"
 

include/ToolTip.h

@@ -1,42 +0,0 @@
-/*
- * ToolTip.h - namespace toolTip, a tooltip-wrapper for LMMS
- *
- * Copyright (c) 2005-2008 Tobias Doerffel <tobydox/at/users.sourceforge.net>
- *
- * This file is part of LMMS - https://lmms.io
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program (see COPYING); if not, write to the
- * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
- * Boston, MA 02110-1301 USA.
- *
- */
-
-
-#ifndef TOOLTIP_H
-#define TOOLTIP_H
-
-#include <qstring.h>
-
-#include "lmms_export.h"
-
-class QWidget;
-
-
-struct ToolTip
-{
-	static void LMMS_EXPORT add( QWidget * _w, const QString & _txt );
-} ;
-
-
-#endif