Fix the 250 chars memcached cache key limit on symfony 1

WhateverToolkit.class.php

<?php
  /**
   * Set cache_namespace_callable: [ pouet, generateShortenedCacheKey ] in your settings.yml
   * Then the symfony cache key is shortened by MD5
   *
   * @author dalexandre
   * @see sfViewCacheManager::generateCacheKey
   * @param sfViewCacheManager $sfViewCacheManager
   * @return string
   */
  public static function generateShortenedCacheKey($internalUri, $hostName, $vary, $contextualPrefix, $sfViewCacheManager)
  {
    // Store and destroy the callable param, because we want to use the internal generated key.
    $sfconfig = sfConfig::get('sf_cache_namespace_callable');
    sfConfig::set('sf_cache_namespace_callable', false);
    
    $key = md5($sfViewCacheManager->generateCacheKey($internalUri, $hostName, $vary, $contextualPrefix));

    // Restaure the initial config and return the short key
    sfConfig::set('sf_cache_namespace_callable', $sfconfig);
    return $key;
  }