PathExtentsToMaxStrokeExtents currently just uses GetCanvasTM() to figure out how much to expand the stroke by. When calling GetBBoxContribution, this can mean that we get the expansion very wrong, since the transform to the canvas is not usually what we want.
The kill-covered-regions patches in bug 614732 switch to using GetBBoxContribution in user space (instead of canvas space) as part of figuring out the covered region, and some tests fail as a result of PathExtentsToMaxStrokeExtents using the canvas TM.
Created attachment 595925 [details] [diff] [review]
This patch also depends on the changes to test_bounds.html in bug 725897.