Set Z-position correctly for wxEVT_JOY_ZMOVE events.

Z-move events don't have (x, y) position, but they do have Z-position which
needs to be set.

Also don't use (x, y) position for these events in the sample.

See #748.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70279 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/window.cpp

@@ -5950,7 +5950,10 @@ bool wxWindowMSW::HandleJoystickEvent(WXUINT msg, int x, int y, WXUINT flags)
     }
 
     wxJoystickEvent event(eventType, buttons, joystick, change);
-    event.SetPosition(wxPoint(x, y));
+    if ( eventType == wxEVT_JOY_ZMOVE )
+        event.SetZPosition(x);
+    else
+        event.SetPosition(wxPoint(x, y));
     event.SetEventObject(this);
 
     return HandleWindowEvent(event);