Bug 691321

With the changes in gsptype1.c rev5391 and the fact that, per the PS spec, we use centered pixel rendering for images and any part of pixel rendering for graphics, the filling of the bits buffer for the cached tile may have different elements filled if we filled with an image versus a solid color.  Since we really should have the same pixels filled in the pattern buffer regardless if a path is filled with an image or a solid color we probably should use any part of pixel rendering for images and graphics.   irc discussion about this Tuesday May 18th 2010.