[cairo] win32 font faces

[Ian Britten]

Adrian Johnson wrote:
> Bug 24849 reports that Inkscape on win32 is creating PDFs with the same 
> font embedded multiple times.

FYI - I encountered a similar problem with custom/user fonts being
embedded multiple times in PDFs.  (Or was it with FT fonts?  Or was
it both?  I don't recall at the moment.)  However, I had to end up
filtering out duplicates myself...

   [ snip ]
> Would it be better to filter out duplicate LOGFONTS in 
> cairo-scaled-font-subsets.c instead to guarantee fonts will only be 
> embedded once?

Would this alternate fix be limited to just win32/LOGFONTS, or would
it filter out any/all duplicates (Including user fonts)?

I don't particularly _need_ it, since my code is in place, and I have
to do some caching anyways to prevent dangling pointers, but if this
affected my case, I'd probably review/revise my code accordingly.

Ian