Windows: Fix resource leak

Task-number: QTCREATORBUG-7385

Change-Id: I9c6e72a83e8761d32b1f9f94594e4e5d22f48b28
Reviewed-by: Daniel Molkentin <daniel.molkentin@nokia.com>

src/plugins/coreplugin/progressmanager/progressmanager_win.cpp

@@ -134,6 +134,7 @@ void Core::Internal::ProgressManagerPrivate::setApplicationLabel(const QString &
         const HICON icon = pix.toWinHICON();
 #endif
         pITask->SetOverlayIcon(winId, icon, (wchar_t*)text.utf16());
+        DestroyIcon(icon);
     }
 }