Revert "Add _scenegraphLoader property to ScenegraphLayer (#3258)"

This reverts commit e443afe.

docs/layers/scenegraph-layer.md

@@ -71,11 +71,6 @@ Can be a URL of an object. You need to provide the `fetch` function to load the
 Can also be a luma.gl [ScenegraphNode](http://uber.github.io/luma.gl/#/documentation/api-reference/), or a `Promise` that resolves to one.
 The layer calls _delete()_ on _scenegraph_ when a new one is provided or the layer is finalized.
 
-##### `_scenegraphLoader` (Object, optional)
-
-If you provide a URL for `scenegraph` you can optionally provide a `_scenegraphLoader` to load the URL.
-Read more about loaders [here](https://loaders.gl/docs/developer-guide/get-started).
-If not provided `loaders.gl` will select one automatically from [registered loaders](https://loaders.gl/docs/api-reference/core/register-loaders).
 
 ### Render Options
 

modules/mesh-layers/src/scenegraph-layer/scenegraph-layer.js

@@ -34,16 +34,10 @@ const DEFAULT_COLOR = [255, 255, 255, 255];
 
 const defaultProps = {
   scenegraph: {type: 'object', value: null, async: true},
-  _scenegraphLoader: null,
 
   fetch: (url, {propName, layer}) => {
     if (propName === 'scenegraph') {
-      const options = layer.getLoadOptions();
-
-      if (layer.props._scenegraphLoader) {
-        return load(url, layer.props._scenegraphLoader, options);
-      }
-      return load(url, options);
+      return load(url, layer.getLoadOptions());
     }
 
     return fetch(url).then(response => response.json());

test/modules/layers/scenegraph-layer.spec.js

@@ -126,25 +126,3 @@ test('ScenegraphLayer#tests', t => {
 
   t.end();
 });
-
-test('ScenegraphLayer#defaultProps.fetch', async t => {
-  const loadOptions = {
-    load: true
-  };
-  const url = new ArrayBuffer();
-  const propName = 'scenegraph';
-  const layer = {
-    props: {
-      _scenegraphLoader: {
-        parse: () => 9,
-        loadAndParse: () => 9,
-        extensions: '.glb'
-      }
-    },
-    getLoadOptions: () => loadOptions
-  };
-
-  const loaded = await ScenegraphLayer.defaultProps.fetch(url, {propName, layer});
-  t.ok(loaded === 9, 'Using loader success');
-  t.end();
-});