R1:5520dbfac6cc

Quicksand and Pholio - make mock edit work

Summary: Fixes T8036. In addition to making the mock edit work, this tightens quicksand code such that the correct page id is returned even if start() has not been called yet. It also tightens mock view where some functions should respect statics.enabled a bit more.

Test Plan:
clicked edit mock, mock crumb, edit mock, mock crum, edit mock, made edits and they worked! clicked edit mock, mock crumb, edit mock, mock crumb, edit mock, profile icon, hit browser back…