Add orig_h and orig_w to CropTransform to enable inverse transform

Summary:
Pull Request resolved: https://github.com/facebookresearch/d2go/pull/244

Inverse transform of ``CropTransform`` requires knowing the original h and w. Add ``orig_h`` and ``orig_w`` to ``CropTransform`` so inverse transform can be used.

Reviewed By: wat3rBro

Differential Revision: D36321451

fbshipit-source-id: 4382de808724d48d71aafe458e05bba400bf6c6b

d2go/data/transforms/crop.py

@@ -227,7 +227,9 @@ class RandomInstanceCrop(aug.Augmentation):
         bbox_xywh = bu.scale_bbox_center(bbox_xywh, scale)
         bbox_xywh = bu.clip_box_xywh(bbox_xywh, image_size).int()
 
-        return CropTransform(*bbox_xywh.tolist())
+        return CropTransform(
+            *bbox_xywh.tolist(), orig_h=image_size[0], orig_w=image_size[1]
+        )
 
 
 # example repr: "RandomInstanceCropOp::{'crop_scale': [0.8, 1.6]}"