The additional 8 bits of integer allows device space to be 256
times larger before applications need to start worrying about
any issues with overflow. So this should help in many cases.
And the loss of 8 bits of sub-pixel precision shouldn't cause
any harm at all---16 was really much more than necessary.
With this change the details of rasterization for several tests
are changed slightly, (particularly on arcs, for example), so
many reference images are updated here.
NOTE: This change is currently breaking get-path-extents for
ps/pdf/svg as well as push-group for ps. We do not yet know
the reasons for these new failures.
The purpose of this test case is to help make
sure that changes to the trapezoid generation or
intersection computation in the tessellator
don't break it.