Facebook Graph API v2.3 のアップグレードにより互換性の問題が発生するのはなぜですか?

https://graph.facebook.com/v2.3/{$user_id}?date_format=U&fields=albums.order(reverse_chronological).limit(100).offset(0){id,count,name,created_time}

https://graph.facebook.com/v2.3/{$user_id}

$response = json_decode($access_token_response);
if (!isset($response->access_token)) {
  return false;
}
return $response->access_token;

public function setExtendedAccessToken() {
try {
    // need to circumvent json_decode by calling _oauthRequest
    // directly, since response isn't JSON format.
    $access_token_response = $this->_oauthRequest(
        $this->getUrl('graph', '/oauth/access_token'),
        $params = array(
            'client_id' => $this->getAppId(),
            'client_secret' => $this->getAppSecret(),
            'grant_type' => 'fb_exchange_token',
            'fb_exchange_token' => $this->getAccessToken(),
        )
    );
} catch (FacebookApiException $e) {
    // most likely that user very recently revoked authorization.
    // In any event, we don't have an access token, so say so.
    return false;
}

if (empty($access_token_response)) {
    return false;
}

//Version 2.3 and up.
$response = json_decode($access_token_response);
if (!isset($response->access_token)) {
    return false;
}

$this->destroySession();

$this->setPersistentData(
    'access_token', $response->access_token
);
}