function computeCachedCssStaggerStyles(node, className, cacheKey, properties) {
      var stagger;
      var staggerCacheKey = 'stagger-' + cacheKey;

      // if we have one or more existing matches of matching elements
      // containing the same parent + CSS styles (which is how cacheKey works)
      // then staggering is possible
      if ($$animateCache.count(cacheKey) > 0) {
        stagger = $$animateCache.get(staggerCacheKey);

        if (!stagger) {
          var staggerClassName = pendClasses(className, '-stagger');

          $$jqLite.addClass(node, staggerClassName);

          stagger = computeCssStyles($window, node, properties);

          // force the conversion of a null value to zero incase not set
          stagger.animationDuration = Math.max(stagger.animationDuration, 0);
          stagger.transitionDuration = Math.max(stagger.transitionDuration, 0);

          $$jqLite.removeClass(node, staggerClassName);

          $$animateCache.put(staggerCacheKey, stagger, true);
        }
      }

      return stagger || {};
    }
@ngdoc function
@name pascalprecht.translate.$translateProvider#storagePrefix
@methodOf pascalprecht.translate.$translateProvider

@description
Sets prefix for storage key.

@param {string} prefix Storage key prefix