[LyX/master] Compile fix for Qt < 5.7

[Juergen Spitzmueller]

commit 7c31bfa423c2da7c41f53ecde6c159fca35f3d54
Author: Juergen Spitzmueller <sp...@lyx.org>
Date:   Fri Dec 21 13:37:07 2018 +0100

    Compile fix for Qt < 5.7
    
    Only after that version, the QAction argument is optional.
---
 src/frontends/qt4/GuiCharacter.h |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/frontends/qt4/GuiCharacter.h b/src/frontends/qt4/GuiCharacter.h
index ca55f33..40da643 100644
--- a/src/frontends/qt4/GuiCharacter.h
+++ b/src/frontends/qt4/GuiCharacter.h
@@ -112,9 +112,9 @@ private:
        bool nospellcheck_;
 
        ///
-       QAction * resetdefault_ = new QAction;
+       QAction * resetdefault_ = new QAction(this);
        ///
-       QAction * resetnochange_ = new QAction;
+       QAction * resetnochange_ = new QAction(this);
 };
 
 } // namespace frontend