Returns TRUE if tag is toggled off at exactly this point. If tag
is NULL, returns TRUE if any tag is toggled off at this point.
Note that if gtk_text_iter_ends_tag() returns TRUE, it means that iter is
at the end of the tagged range, but that the character
at iter is outside the tagged range. In other words,
unlike gtk_text_iter_begins_tag(), if gtk_text_iter_ends_tag() returns TRUE,
gtk_text_iter_has_tag() will return FALSE for the same parameters.
Returns TRUE if tag is toggled off at exactly this point. If tag is NULL, returns TRUE if any tag is toggled off at this point. Note that if gtk_text_iter_ends_tag() returns TRUE, it means that iter is at the end of the tagged range, but that the character at iter is outside the tagged range. In other words, unlike gtk_text_iter_begins_tag(), if gtk_text_iter_ends_tag() returns TRUE, gtk_text_iter_has_tag() will return FALSE for the same parameters.