Add any special tokens this field might use for itself.
This method is intended to be overridden by items that generate fields as a list. For example, the field that displays all terms on a node might have tokens for the tid and the term.
By convention, tokens should follow the format of [token-subtoken] where token is the field ID and subtoken is the field. If the field ID is terms, then the tokens might be [terms-tid] and [terms-name].
Overrides FieldPluginBase::addSelfTokens
protected function addSelfTokens(&$tokens, $item) {
foreach (array(
'tid',
'name',
'vocabulary_vid',
'vocabulary',
) as $token) {
// Replace _ with - for the vocabulary vid.
$tokens['[' . $this->options['id'] . '-' . str_replace('_', '-', $token) . ']'] = isset($item[$token]) ? $item[$token] : '';
}
}