Fix redraw problems in preview frames and debug panel
The problem was that direct call of RefreshView (now DrawView) doesn't
generate EVT_PAINT (at least on GNU/Linux with Wayland and wxgtk build
with gtk3+ support).
Now RefreshView simply triggers EVT_PAINT and EVT_PAINT handler does actual work.
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# See COPYING.Runtime file for copyrights details.