Please describe the problem:
When raise_on_click is false certain windows don't get focus when they are opened so they get placed behind the focus window, often meaning they are completely obscured and it appears as if nothing has happened. When raise_on_click is True, or when using other window managers, these same windows get focused and placed at the top of the stack.

I think this is a side-effect of meta_window_notify_focus() calling meta_display_(un)grab_focus_window_button() because if I stop it from doing that the problem goes away but I don't understand the grabbing issue well enough to come up with a proper fix.

Steps to reproduce:
1. Configure with metacity raise_on_click = 0 (and focus_mode = sloppy or mouse)
2. Open claws-mail
3. Click Compose


Actual results:
Claws-mail's main window keeps the focus and the compose dialog opens behind it.

Expected results:
The compose dialog should be focused and opened above the other window(s).

Does this happen every time?
The problem is repeatable each time I re-run claws-mail, but if I close the compose dialog and open it again it opens focused and raised.

Other information:
As well as the claws-mail example another situation I've found triggers the problem is a case where in response to a dialog button being clicked a dbus message is sent to another program, asking it to open another dialog, which is modal; the first program blocks on the dbus call, so its dialog doesn't get closed until the second program closes its dialog, and with metacity and raise_on_click = 0 the first dialog keeps focus instead of the second one grabbing it.