angular/watchtower.js — pull request #18 by caitp (2014-03-24 00:44:17+00:00)
Title: fix(watchgroup): also support method invocation on the empty string

0965401fa009718e8f4aabda4f279884efaec646 added support for method invocation
on primitive types, however the empty string is treated as a null value, and
is neglected. While there is no good reason to call a method on the empty
string, it is now possible.