public function testVariantTypes()
 {
     $file = new Google_Service_Drive_DriveFile();
     $metadata = new Google_Service_Drive_DriveFileImageMediaMetadata();
     $metadata->setCameraMake('Pokémon Snap');
     $file->setImageMediaMetadata($metadata);
     $data = json_decode(json_encode($file->toSimpleObject()), true);
     $this->assertEquals('Pokémon Snap', $data['imageMediaMetadata']['cameraMake']);
 }