[ASTableView] Add Optional constrainedSizeForRowAtIndexPath: Data Source Method

[Adlai-Holler]

This would correspond to the ASCollectionDataSource method

- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath;

The widths in the returned size range would be ignored. This would make it easy for the data source to specify min/max row heights.

• Add the optional selector to the ASTableDataSource protocol with documentation.
• Add a test that the returned size is enforced.
• Add a flag for whether the data source responds to the selector.
• In -[ASTableView dataController:constrainedSizeForNodeAtIndexPath:], check that flag and consult the data source if possible otherwise use the current unconstrained values.

I can tackle this in the next couple days but if someone else has bandwidth go for it!

[levi]

We also need this for collection views if we are going to have the cells self-size before the layout accesses them.

[appleguy]

@levi it does exist for collection today, right? just checking.

@Adlai-Holler thanks for filing this. @nguyenhuy confirmed it would be easy to add after his recent refactor, so we should try to do this in the next month before 2.0GM.

[appleguy]

PR #1769 closes this issue.