GitLab

This assertion was removed in 1c349c62
because the assumption was invalid during set_intervals_multibyte_1.
So we change set_intervals_multibyte_1 to solve the problem in the same
way as in the rest of Fset_buffer_multibyte, which actually simplifies
the code.

* src/buffer.c (advance_to_char_boundary): Not static any more.
* src/buffer.h (advance_to_char_boundary): Add prototype.
* src/intervals.c (set_intervals_multibyte_1): Use it.