With this patch the window manager related functionality is split out
onto a new endpoint pair named WindowManagerServer/Client. This allows
window manager functionality to be potentially privilege separated in
the future. To this end, a new client named WMConnectionClient
is used to maintain a window manager connection. When a process
connects to the endpoint and greets the WindowServer as a window manager
(via Window::make_window_manager(int)), they're subscribed to the events
they requested via the WM event mask.
This patch also removes the hardcoding of the Taskbar WindowType to
receive WM events automatically. However, being a window manager still
requires having an active window, at the moment.
WindowServer now collects applet windows into an "applet area" which is
really just a window that a WM (window management) client can position
via IPC.
This is rather hackish, and I think we should come up with a better
architecture eventually, but this brings back the missing applets since
the global menu where they used to live is gone.