Type improvements

Summary: some type simplifications, that makes it easier to reuse data sources and helps type inference

Reviewed By: passy

Differential Revision: D28413380

fbshipit-source-id: 261a8b981bf18a00edc3075926bd668322e1c37d

desktop/flipper-plugin/src/data-source/DataSourceRendererVirtual.tsx

@@ -39,7 +39,7 @@ type DataSourceProps<T extends object, C> = {
   /**
    * The data source to render
    */
-  dataSource: DataSource<T, any, any>;
+  dataSource: DataSource<T>;
   /**
    * Automatically scroll if the user is near the end?
    */