update INJECTED_COCO_DATASETS_LUT when registering AdhocCOCODataset

Summary:
Pull Request resolved: #584

When registering AdhocCOCODataset, INJECTED_COCO_DATASETS_LUT needs to be updated as well.
For example, if a dataset uses custom registering function, it can be only retrieved from INJECTED_COCO_DATASETS_LUT.
Otherwise, it uses the default registering function as in branch `register_dataset_split`.

Reviewed By: antonrigner

Differential Revision: D46826507

fbshipit-source-id: 31bc5c79e3b82a20cb798dec37b18d9271040cdf

Author: stephenyan1231

d2go/data/utils.py

@@ -20,6 +20,7 @@
     ANN_FN,
     IM_DIR,
     INJECTED_COCO_DATASETS_LUT,
+    InjectedCocoEntry,
     register_dataset_split,
 )
 from detectron2.data import DatasetCatalog, MetadataCatalog
@@ -168,9 +169,10 @@ def register_catalog(self):
             DatasetCatalog.register(self.new_ds_name, new_func)
         elif self.src_ds_name in INJECTED_COCO_DATASETS_LUT:
             _src_func, _src_dict = INJECTED_COCO_DATASETS_LUT[self.src_ds_name]
-            _src_func(
-                self.new_ds_name,
-                split_dict={**_src_dict, ANN_FN: tmp_file, IM_DIR: metadata.image_root},
+            split_dict = {**_src_dict, ANN_FN: tmp_file, IM_DIR: metadata.image_root}
+            _src_func(self.new_ds_name, split_dict=split_dict)
+            INJECTED_COCO_DATASETS_LUT[self.new_ds_name] = InjectedCocoEntry(
+                func=_src_func, split_dict=split_dict
             )
         else:
             # NOTE: only supports COCODataset as DS_TYPE since we cannot reconstruct