Mac:Closing a child dialog causes the main window to be incorrectly brought to front

Child Dialog is always displayed behind parent window, Further if Grand child dialog of main window is closed Main window popsup in front.

To reproduce:
1) Left click on child window to spawn a third dialog.
2) Close the third dialog
3) Notice that the main window is brought to front rather than the child window that parented the third dialog.

This is regression from Qt4 to 5.