Remove cairo_scaled_glyph_t::dev_private and dev_private_key
See !476 (merged) and #778 (closed).
While it is possible to use these fields semi-safely, one has to remember to always check whether dev_private_key
still matches or otherwise one could access the private data of some other piece of code.
Since the API around the dev_privates
fields exists and provides basically the same experience, but without multiple users overwriting each other's data, it seems like the safest thing to do would be to just remove dev_private
and dev_private_key
and change all existing users to _cairo_scaled_glyph_attach_private()
and ..._find_private()
.