emberjs/ember.js — pull request #3361 by hjdivad (2013-09-08 21:06:39+00:00)
Title: Fire observers for array computed changes.

When dealing with chains of arrays, it is not necessary (or correct) to
fire non-array observers when array contents change, but the array itself
does not.

However, for other `ReduceComputedProperty`s, such as
`Ember.computed.max`, it is necessary to fire observers in response to
upstream array changes.

Thanks @ssured for pointing this out, and for providing tests!