Change in tst_qstylesheetstyle.cpp to work around a bug in testcocoon parser.

Change-Id: I1361e4c02e0c8a0424957c531e22a7b2236f725d
Reviewed-on: http://codereview.qt.nokia.com/4360
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>

tests/auto/qstylesheetstyle/tst_qstylesheetstyle.cpp

@@ -1650,7 +1650,7 @@ void tst_QStyleSheetStyle::QTBUG11658_cachecrash()
 
 void tst_QStyleSheetStyle::QTBUG15910_crashNullWidget()
 {
-    struct : QWidget {
+    struct Widget : QWidget {
         virtual void paintEvent(QPaintEvent* ) {
             QStyleOption opt;
             opt.init(this);