Help mode: don't hide the frame for the open pages switcher

Also removed a superfluous elide mode setter.

Reviewed-by: kh1

src/plugins/help/openpageswidget.cpp

@@ -90,7 +90,6 @@ OpenPagesWidget::OpenPagesWidget(OpenPagesModel *model, QWidget *parent)
     setIndentation(0);
     setItemDelegate((m_delegate = new OpenPagesDelegate(this)));
 
-    setFrameStyle(QFrame::NoFrame);
     setTextElideMode(Qt::ElideMiddle);
     setAttribute(Qt::WA_MacShowFocusRect, false);