Adapts display specifications to the current run-time context.
The functionality has moved to the FieldInfo class. This function is kept as a backwards-compatibility layer. See http://drupal.org/node/1915646.
FieldInfo::prepareInstanceDisplay()
function _field_info_prepare_instance_display($field, $display) {
$cache = _field_info_field_cache();
return $cache
->prepareInstanceDisplay($display, $field['type']);
}