Reg[4-5] Windows: Child dialog shows again on restoring transient parent when hide() was called while transient parent was minimized

If a child dialog which is iconified is closed/hide programmatically, up on activation still shows and clicking on close button has no effect.

Attached example reproduces it:
Steps:
Run the example
Click on button to minimize all widget
wait for 5 second (when timer fires and dialog is set to close/hide)
click on iconified window in task bar
Child dialog still visible and closing it with mouse has no effect.

This works good with Qt4