E10s compat for basic operation

git-svn-id: https://code.downthemall.net/repos/trunk@3770 43940e1f-b481-bb45-89eb-5c6a4bf3d40a
Backwards compat for non-e10s in integration

git-svn-id: https://code.downthemall.net/repos/trunk@3771 43940e1f-b481-bb45-89eb-5c6a4bf3d40a
Switch to native Promise in FilterManager

git-svn-id: https://code.downthemall.net/repos/trunk@3772 43940e1f-b481-bb45-89eb-5c6a4bf3d40a
Switch over to native promises
And simplify chunk handling in the process

git-svn-id: https://code.downthemall.net/repos/trunk@3773 43940e1f-b481-bb45-89eb-5c6a4bf3d40a