Fix generate with inputs_embeds as input (#32493)

* I think inputs_embeds has ndim == 3

* fix sequence length catch

* add generate test

* [run-slow]olmo, persimmon, gemma, gemma2, qwen2, llama

* skip whisper

* fix bart test

* more fixes

tests/models/whisper/test_modeling_whisper.py

@@ -4058,6 +4058,11 @@ class WhisperStandaloneDecoderModelTest(ModelTesterMixin, GenerationTesterMixin,
         # generate only works with input ids for whisper
         pass
 
+    @unittest.skip(reason="Generate needs input ids")
+    def test_inputs_embeds_matches_input_ids_with_generate(self):
+        # generate only works with input ids for whisper
+        pass
+
     @unittest.skip(reason="Decoder can't keep attention grads")
     def test_retain_grad_hidden_states_attentions(self):
         return