fix a bug in D2GoDatasetMapper

Summary:
Pull Request resolved: https://github.com/facebookresearch/d2go/pull/101

In D2 (https://github.com/facebookresearch/d2go/commit/4f3f3401173ee842995ec69a7ce2635e2deb178a)GoDatasetMapper, when crop transform is applied to the image. "Inputs" should be updated to use the cropped images before other transforms are applied later.

Reviewed By: zhanghang1989

Differential Revision: D29551488

fbshipit-source-id: 48917ffc91c8a80286d61ba3ae8391541ec2c930

d2go/data/dataset_mappers/d2go_dataset_mapper.py

@@ -122,7 +122,7 @@ class D2GoDatasetMapper(object):
                     image.shape[:2],
                     np.random.choice(dataset_dict["annotations"]),
                 )
-                image = crop_tfm.apply_image(image)
+                inputs.image = crop_tfm.apply_image(image)
             transforms = AugmentationList(self.tfm_gens)(inputs)
             image = inputs.image
             if self.crop_gen: