fix(rootScope, ngRepeat): add support for objects created with Object.create(null) for ngRepeat and $watchCollection

Basically, the hasOwnProperty method was being called from an object gotten from the user. When that object was initially created with Object.create(null), it didn't inherit from Object so it didn't have the hasOwnProperty method throwing an "undefined is not a function" error. 

This was fixed by executing hasOwnProperty.call(object, key) instead of object.hasOwnProperty(key)