GPU contexts can hold on to a significant amount of resources. Clean
them up immediately instead of at test cleanup.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The clear background is the most useful, and the old behaviour can
be achieved by filling the entire viewport with a white paint.ColorOp.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The new compute renderer can draw simple strokes. Test that clipping
works with a stroke basis, and that images can be drawn into strokes.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur