code: function(oRequest, oResponse) {
      var aCache = this._aCache;
      if(!aCache) {
          return;
      }
  
      // If the cache is full, make room by removing stalest element (index=0)
      while(aCache.length >= this.maxCacheEntries) {
          aCache.shift();
      }
  
      // Add to cache in the newest position, at the end of the array
      var oCacheElem = {request:oRequest,response:oResponse};
      aCache[aCache.length] = oCacheElem;
      this.fireEvent("responseCacheEvent", {request:oRequest,response:oResponse});
  }
docs: Adds a new item to the cache. If cache is full, evicts the stalest item
  before adding the new item.
  
  @method addToCache
  @param oRequest {Object} Request object.
  @param oResponse {Object} Response object to cache.