[LyX/master] amend 99b1488f0e591539b5597d36dbadda26844b2078 - on Mac the include is needed

[Stephan Witt]

commit 7b41faabaea7fcecee676bb4b12cbae8bb3da558
Author: Stephan Witt <switt at lyx.org>
Date:   Fri Dec 11 18:42:04 2020 +0100

    amend 99b1488f0e591539b5597d36dbadda26844b2078 - on Mac the include is needed
---
 src/frontends/qt/GuiKeySymbol.cpp |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/src/frontends/qt/GuiKeySymbol.cpp b/src/frontends/qt/GuiKeySymbol.cpp
index b55f890..2cd2f61 100644
--- a/src/frontends/qt/GuiKeySymbol.cpp
+++ b/src/frontends/qt/GuiKeySymbol.cpp
@@ -11,6 +11,9 @@
 #include <config.h>
 
 #include "GuiKeySymbol.h"
+#if defined(Q_OS_MAC) && QT_VERSION > 0x050000
+#include "GuiApplication.h"
+#endif
 #include "qt_helpers.h"
 
 #include "support/lassert.h"