Like the other blitters. When the GLSL blitter was introduced, the idea was
that caller would be responsible for doing this, but we never ended up
updating the other blitters.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=49251Signed-off-by: Paul Gofman <pgofman@codeweavers.com>
Signed-off-by: Henri Verbeet <hverbeet@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>