Use showNormal() instead of show() in QToolTip.

Even on platforms that use the QPlatformIntegration::StyleHint
ShowIsFullScreen we do not want to show tool tips fullscreen which
would happen if we just call show().

This is also required to fix somewhat random crashes on QNX when
browsing a website and hovering links that would trigger a tooltip to
be shown. There, we could end up with nested calls to
QToolTip::showText when the tooltip was shown full-screen. Since
QToolTip is not reentrant that can lead to crashes since
QTipLabel::instance could be deleted/invalidated inbetween.

Change-Id: I335fcd10cb6d4cffeb622ed8e0caf17f6413d62d
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

src/widgets/kernel/qtooltip.cpp

@@ -512,9 +512,9 @@ void QToolTip::showText(const QPoint &pos, const QString &text, QWidget *w, cons
         else if (QApplication::isEffectEnabled(Qt::UI_AnimateTooltip))
             qScrollEffect(QTipLabel::instance);
         else
-            QTipLabel::instance->show();
+            QTipLabel::instance->showNormal();
 #else
-        QTipLabel::instance->show();
+        QTipLabel::instance->showNormal();
 #endif
     }
 }