TextEditor: Use Qt5-style connects

The heavy lifting was done by clazy.

Change-Id: I380120e3419d2a3c0e272f51cc3e0d5f6aaa5e9b
Reviewed-by: Tobias Hunger <tobias.hunger@theqtcompany.com>

src/plugins/texteditor/codeassist/functionhintproposalwidget.h

@@ -61,11 +61,9 @@ public:
 protected:
     bool eventFilter(QObject *o, QEvent *e) override;
 
-private slots:
+private:
     void nextPage();
     void previousPage();
-
-private:
     bool updateAndCheck(const QString &prefix);
     void updateContent();
     void updatePosition();