PangoCairo refactoring

[Behdad Esfahbod <behdad behdad org>]

Hi Tor and Richard,

I finally finished and committed a patch I had lying around to move most
of the code from pangocairo-fcfont.c into pangocairo-font.c.  It mostly
includes glyph extents cache but also other bits that is generic in
cairo.  With the new code, the only methods that a PangoCairo*Font class
needs to implement are create_font_face() and
create_metrics_for_context().  Please go ahead and fix ATSUI and Win32
implementations as they do not compile anymore.  I'm sure it will be
trivial to adapt, and should rip some duplicated code out.

Cheers,
-- 
behdad
http://behdad.org/

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