Story 1462: Move new overlay code and new editor to stable

Also, add browser tests for opening and closing the editor.

Change-Id: Id5070b053ca74c2b05ad149e0bdc4c2931a304dc
Story 1462: Move new uploads overlay to stable

Also, add browser tests for opening and closing the overlay.

Change-Id: I60e9bbe6d08609444301e29691aa797f533d67d2