It was added without proper measurement and a fuzzy possible
use-case (font servers) in mind, but reality check shows that
this significantly slows down caching. As such, deprecate it
and do NOT compute hash during caching.
Makes caching two to three times faster (ignoring the 2 second
delay in fc-cache).
This feature requires the FreeType 2.5.1 or later at the build time.
Besides <range> element allows <double> elements with this changes.
This may breaks the cache but not bumping in this change sets at this moment.
please be aware if you want to try it and run fc-cache before/after to
avoid the weird thing against it.
Workaround to not failing even when the hash is unable to generate from fonts.
This change also contains to ignore the case if the hash isn't in either both
patterns.
Behdad Esfahbod
Akira TAGOH