Add missing include to qwebenginesettings.h

Change-Id: I9c0dd4e2da5452e6d90f177f4c5d5edd735294e5
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>

src/webenginewidgets/api/qwebenginesettings.h

@@ -22,6 +22,7 @@
 #define QWEBENGINESETTINGS_H
 
 #include <QtWebEngineWidgets/qtwebenginewidgetsglobal.h>
+#include <QtCore/qscopedpointer.h>
 #include <QtCore/qstring.h>
 
 QT_BEGIN_NAMESPACE