/**
* Removing unused language elements from database.
* @return integer The number of removed language elements.
*/
public function run()
{
$this->_scanner = new Scanner();
$this->_scanner->run();
$this->_scanner->stdout('Deleted language elements - BEGIN', Console::FG_RED);
$languageSourceIds = $this->_scanner->getRemovableLanguageSourceIds();
$this->_initLanguageElements($languageSourceIds);
LanguageSource::deleteAll(['id' => $languageSourceIds]);
$this->_scanner->stdout('Deleted language elements - END', Console::FG_RED);
return count($languageSourceIds);
}