js/libs/ember-1.5.1.js
function(context, callback) {
    var pair;
    if (!this.waiters) { return; }
    if (arguments.length === 1) {
      callback = context;
      context = null;
    }
    pair = [context, callback];
    this.waiters = Ember.A(this.waiters.filter(function(elt) {
      return Ember.compare(elt, pair)!==0;
    }));
  }
function(context, callback) {
    var pair;
    if (!this.waiters) { return; }
    if (arguments.length === 1) {
      callback = context;
      context = null;
    }
    pair = [context, callback];
    this.waiters = Ember.A(this.waiters.filter(function(elt) {
      return Ember.compare(elt, pair)!==0;
    }));
  }
`unregisterWaiter` is used to unregister a callback that was
registered with `registerWaiter`.

@public
@method unregisterWaiter
@param {Object} context (optional)
@param {Function} callback