[truetype] Restore behavior of ft_var_load_hvvar
- src/truetype/ttgcvar.c (ft_var_load_hvvar): restore previous behavior
In a previous change [0] the behavior of ft_var_load_hvvar was changed
to not load the item variation store if it was at offset 0, but not
return an error when this happened. This broke any users, like
tt_hvadvance_adjust, that rely on successful completion of
ft_var_load_hvvar to imply that returned table's itemStore had been
initialized. This lead such users to dereference NULL.
This change appears to have been unintentional and unrelated to the
actual avar2 changes. As a result, fix these NULL dereferences by
restoring the code to always attempt to initialize the itemStore.
[0] ae4eb996 "[truetype] Add support for avar table 2.0 format."
Reported as