update relative positional embedding (#20203)

* update relative positional embedding

* make fix copies

* add `use_cache` to list of arguments

* fixup

* 1line fucntion

* add `test_decoder_model_past_with_large_inputs_relative_pos_emb`

* add relative pos embedding test for more models

* style

tests/models/xlm_roberta_xl/test_modeling_xlm_roberta_xl.py

@@ -431,6 +431,11 @@ class XLMRobertaXLModelTest(ModelTesterMixin, GenerationTesterMixin, unittest.Te
         config_and_inputs = self.model_tester.prepare_config_and_inputs_for_decoder()
         self.model_tester.create_and_check_decoder_model_past_large_inputs(*config_and_inputs)
 
+    def test_decoder_model_past_with_large_inputs_relative_pos_emb(self):
+        config_and_inputs = self.model_tester.prepare_config_and_inputs_for_decoder()
+        config_and_inputs[0].position_embedding_type = "relative_key"
+        self.model_tester.create_and_check_decoder_model_past_large_inputs(*config_and_inputs)
+
     def test_for_masked_lm(self):
         config_and_inputs = self.model_tester.prepare_config_and_inputs()
         self.model_tester.create_and_check_for_masked_lm(*config_and_inputs)