code: function callObservers(object, chgeset) {
      var ln = object[OBSERVER_PROPERTY];
      if (ln) {
          var elt;
          for (var i = 0, sz = ln.length; sz > i; i++) {
              elt = ln[i];
              if (elt.constructor === Function) {
                  elt(chgeset);
              }
          }
      }
  }
docs: Call all observers for a givent object
  @param {Object} object reference to the object that is being observed
  @param {Array} chgeset an array of change descriptors (cf. changeDesc())