In commit d34ae764769 I switched mutter-window to ask for Raw rectangles
from the X server. This avoided 2 non synchronous and 2 synchronous X
requests per window with damage, per frame; 2 (non-sync) to
create/destroy a temporary region to copy the damage region into, 1 to
request the server to copy the damage region into a our given region and
another to fetch that region back into the client. The problem with raw
events though is that it's possible to DOS the compositor with them.
Instead of receiving an event for every bit of damage this patch instead
asks the server to only report BoundingBox changes to the damage region.
https://bugzilla.gnome.org/show_bug.cgi?id=611838
91d82bf8c7
