richedit: Count graphics towards line width.

Images that are inserted into richedit controls store a space for the
text, since that is the character returned when getting the plain text
from the control.

When calculating the width of a line, the space character is skipped,
but images should not be skipped.  This can be seen by inserting an
image into wordpad on a line by it's own, then centering the line.  The
image will start from the center rather than being centered in the
control.

dlls/riched20/wrap.c

@@ -115,6 +115,7 @@ static void ME_InsertRowStart(ME_WrapContext *wc, const ME_DisplayItem *pEnd)
           WCHAR *text = p->member.run.strText->szData + len - 1;
 
           assert (len);
+          if (~p->member.run.nFlags & MERF_GRAPHICS)
             while (len && *(text--) == ' ')
               len--;
           if (len)