This fixes a subtle bug when the last profile in a contour was not
properly short-circuited if it was still empty at `End_Profile`.
We finalize all linking in `Finalize_Profile_List` now and do nothing
else there. The turns are added in `End_Profile`.
* src/raster/ftraster.c (Insert_Y_Turn): Moved up unchanged.
(End_Profile): Take care of turns but set only preliminary linking.
(Finalize_Profile_Table): Take care of linking and null-termination.
(Convert_Glyph): Adjusted accordingly.
3fa5c84565