bugfix: passing args

Summary: Pull Request resolved: https://github.com/pytorch/fairseq/pull/711

Differential Revision: D15239618

Pulled By: myleott

fbshipit-source-id: 82f3f79501a13a967324b8a66281cd134bf1ef23

fairseq/data/masked_lm_dataset.py

@@ -228,7 +228,10 @@ class MaskedLMDataset(FairseqDataset):
 
                 # mask according to specified probabilities.
                 masked_blk_one, masked_tgt_one = self._mask_block(
-                    s["block_one"], self.mask_idx, self.pad_idx, token_range)
+                    s["block_one"], self.mask_idx, self.pad_idx, token_range,
+                    masking_ratio=self.masking_ratio, masking_prob=self.masking_prob,
+                    random_token_prob=self.random_token_prob,
+                )
 
                 tokens = np.concatenate([
                     [self.classif_token_idx], masked_blk_one