[cairo] Cairo and layered application

[Boris Zbarsky]

Behdad Esfahbod wrote:
> Thanks.  The list really helps.  Fortunately all look very easy to
> optimize as I expected.  I just need a test case that gives
> malloc/realloc numbers so I can measure my progress.

For what it's worth, I'm happy to patch-and-reprofile if that would 
help.  That doesn't scale in general, and separating out the cairo parts 
from the other-Gecko-stuff parts in the profile is a little annoying, so 
it's still good to have tests, of course.

-Boris