angular/angular.js — pull request #10446 by jbedard (2014-12-14 00:30:05+00:00)
Title: fix($compile): use createMap() for $$observe listeners when initialized ...

...from attr interpolation

This alternate initialization of `$$observers` was missed in a27d827c22b0b6b3ba6b7495cf4fc338c6934b37.