Returns the window that is part of the current modal session, if any.
See -runModalForWindow:Processes one event for a modal session described by the theSession variable. Before processing the event, it makes the session window key and orders the window front, so there is no need to do this separately. When finished, it returns the state of the session (i.e. whether it is still running or has been stopped, etc)
See Also: -runModalForWindow:Returns the target object that will respond to aSelector, if any. The method first checks if any of the key window's first responders, the key window or its delegate responds. Next it checks the main window in the same way. Finally it checks the receiver (NSApplication) and it's delegate.