/**
  * Gets the defined field definitions from the ext_tables.sql files.
  *
  * @return array The accordant definitions
  */
 protected function getDefinedFieldDefinitions()
 {
     $content = '';
     $cacheTables = '';
     if (class_exists('t3lib_cache') && method_exists(t3lib_cache, 'getDatabaseTableDefinitions')) {
         $cacheTables = \TYPO3\CMS\Core\Cache\Cache::getDatabaseTableDefinitions();
     }
     if (method_exists($this->install, 'getFieldDefinitions_fileContent')) {
         $content = $this->install->getFieldDefinitions_fileContent(implode(chr(10), $this->getAllRawStructureDefinitions()) . $cacheTables);
     } else {
         $content = $this->install->getFieldDefinitions_sqlContent(implode(chr(10), $this->getAllRawStructureDefinitions()) . $cacheTables);
     }
     return $content;
 }