Utils: Fix painting artifacts of FancyLineEdit on StyledBar

Don't enforce a premature polishing by the style.

Fixes: QTCREATORBUG-27510
Change-Id: I1598a75741c5990567a33ad8376144432894597a
Reviewed-by: Cristian Adam <cristian.adam@qt.io>

src/libs/utils/fancylineedit.cpp

@@ -172,7 +172,6 @@ FancyLineEdit::FancyLineEdit(QWidget *parent) :
     CompletingLineEdit(parent),
     d(new FancyLineEditPrivate(this))
 {
-    ensurePolished();
     updateMargins();
 
     connect(d->m_iconbutton[Left], &QAbstractButton::clicked, this, [this] {