angular/angular.js — pull request #2382 by davidchang (2013-04-12 05:39:40+00:00)
Title: fix(Angular): Angular.copy shouldn't copy $$hashKey or $$* properties

Fix for this issue: https://github.com/angular/angular.js/issues/1875

I copied the code from shallowCopy in to copy so that both should be consistent. Though that issue mentioned Angular.extend also copies $$hashkey, I though that would be appropriate, somewhat expected behavior.