When an an S3 folder containing thousand of assets is expanded, it takes many seconds to render the new assets.
- HierarchicalS3DataProvider.hasChildren calls getChildCount, which will have to count all the items in the folder. We probably should have a dedicate hasChildren method in S3AssetProvider.
- HierarchicalS3DataProvider.fetchChildrenFromBackEnd does not honor the supplied query
The folder is properly displayed, probably rendering assets in batches.