Allow modules to react to language settings changes.
Every module needing to act when the number of enabled languages changes should implement this. This is an "internal" hook and should not be invoked elsewhere. The typical implementation would trigger some kind of rebuilding, this way system components could properly react to the change of the enabled languages number.
Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.
function hook_multilingual_settings_changed() {
field_info_cache_clear();
}