In preparation for adding magnification, "uiGroup.patch", organizes the stage
along the following lines:
Stage
*Magnifier
UI group
Window group
Chrome group
Overlay group
Alt tab
App display
Chrome
...
This allows a magnifier actor to clone and magnify the UI group. The magnifier
is a sibling of the UI Group in this stage oraganization -- see the next patch,
"Magnifier.patch".
Replace the current workspace switcher popup (which is still the old metacity popup), with a clutter based one, which fits better into the overall shell design.
https://bugzilla.gnome.org/show_bug.cgi?id=609187