R1:9c190d68ed37

Separate workboard view state (ordering, filtering, hidden columns) from the View controller

Summary:
Depends on D20627. Ref T4900. If a user orders a board by "Sort by Title", then toggles the visibility of hidden columns, we want to keep the board sorted by title. To accomplish this, we pass the board state around to all the workflows here.

Pull the "bag of state properties" code out of the View controller. This class basically:

- reads state from a request (order, hidden, filter);
- manages…