Remove unused LineEdit slot. Fix compiler warning.

src/gui/lineedit/src/lineedit.cpp

@@ -64,9 +64,9 @@ void LineEdit::resizeEvent(QResizeEvent *e)
 #endif
 }
 
+#if (QT_VERSION < QT_VERSION_CHECK(5, 0, 0))
 void LineEdit::updateCloseButton(const QString &text)
 {
-#if (QT_VERSION < QT_VERSION_CHECK(5, 0, 0))
     clearButton->setVisible(!text.isEmpty());
-#endif
 }
+#endif

src/gui/lineedit/src/lineedit.h

@@ -24,8 +24,10 @@ public:
 protected:
     void resizeEvent(QResizeEvent *e);
 
+#if (QT_VERSION < QT_VERSION_CHECK(5, 0, 0))
 private slots:
     void updateCloseButton(const QString &text);
+#endif
 
 private:
     QToolButton *searchButton;