When the last vertex is coincident with the first vertex, the last
segment should be suppressed for both END_OPEN and END_CLOSED.
Only when last and first vertex are not coincident the additional
line segment may be added - always for intersection tests and
similar, and for stroking operations when the figure is CLOSED.

Trying to use an zero-length segment in d2d_geometry_intersect_self()
will create invalid segments, causing infinite loops later.

Instead of reducing the vertex_count for coincident first/last
vertices add a dedicated type. This is required as some operations
need the last segment, others do not.

This also allows to remove some replicated code in
StrokeContains()/GetBounds()/Simplify(), as a last Bézier segment
is always processed in the regular loop.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=51139Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Henri Verbeet <hverbeet@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>