Per code review comments on 0.16.2, replaced XPCOM Private browsing component with require('private-browsing').
Per code review comments on 0.16.2, replaced XPCOM Private browsing component with require('private-browsing').

Valenchak/lightbeam,mozilla/lightbeam,mozilla/lightbeam,Valenchak/lightbeam,Valenchak/lightbeam,mozilla/lightbeam