[xmonad] Moving windows to the workspace of their parent window

[Mina Nagy Zaki]

I'd like to write a managehook that shifts windows to the workspace of
their parent, without having to restrict that workspace (ie, without
predefining a specific workspace for these windows). For example if I
run skype on one workspace, when I get a call and answer it, I'd like
the call window to automatically shift to the same workspace as skype.
How would I go about this?

-- 
Mina Nagy Zaki