install() {
    // Note that this mock cookie storage does not take into account path,
    // domain and secure flag when manipulating cookies.
    var self = this;
    var r = this.replacer_ = new PropertyReplacer();
    r.replace(
        cookies, 'set', function(key, value, maxAge, path, domain, secure) {
          self.mockCookieStorage_[key] = {
            'value': value,
            'expiration': goog.now() + maxAge * 1000
          };
        });
    r.replace(cookies, 'get', function(key) {
      // Make sure entry exist and is not expired.
      if (self.mockCookieStorage_[key] &&
          self.mockCookieStorage_[key].expiration > goog.now()) {
        return self.mockCookieStorage_[key].value;
      } else {
        delete self.mockCookieStorage_[key];
        return null;
      }
    });
    r.replace(cookies, 'remove', function(key, path, domain) {
      delete self.mockCookieStorage_[key];
    });
    return this;
  }
Installs the fake cookie storage utility.
@return {!FakeCookieStorage} The fake cookie storage utility.