Fix for the ClearType pixel junk in GVIM

Update: This doesn't work for fonts that use the right-most column. In fact the issue seems to be cleartype writing outside the leftmost pixel in the bounding box. :-(

Here's a fix for this super-annoying bug (Lucida Console 11, insert spaces before the C to leave a trail of cleartype pixels).

===================================================================
--- gui_w32.c   (revision 1289)
+++ gui_w32.c   (working copy)
@@ -2234,6 +2234,8 @@
         * Note: FillRect() excludes right and bottom of rectangle.
         */
        rc.left = FILL_X(col);
+       if (rc.left > 0)
+           --rc.left;
        rc.top = FILL_Y(row);
 #ifdef FEAT_MBYTE
        if (has_mbyte)