TFMarian, TFMbart, TFPegasus, TFBlenderbot (#7987)

* Start plumbing

* Marian close

* Small stubs for all children

* Fixed bart

* marian working

* pegasus test is good, but failing

* Checkin tests

* More model files

* Subtle marian, pegasus integration test failures

* Works well

* rm print

* boom boom

* Still failing model2doc

* merge master

* Equivalence test failing, all others fixed

* cleanup

* Fix embed_scale

* Cleanup marian pipeline test

* Undo extra changes

* Smaller delta

* Cleanup model testers

* undo delta

* fix tests import structure

* cross test decorator

* Cleaner set_weights

* Respect authorized_unexpected_keys

* No warnings

* No warnings

* style

* Nest tf import

* black

* Apply suggestions from code review

Co-authored-by: Lysandre Debut <lysandre@huggingface.co>

* functional dropout

* fixup

* Fixup

* style_doc

* embs

* shape list

* delete slow force_token_id_to_be_generated func

* fixup

Co-authored-by: Lysandre Debut <lysandre@huggingface.co>

utils/check_repo.py

@@ -67,6 +67,7 @@ MODEL_NAME_TO_DOC_FILE = {
     "xlm_prophetnet": "xlmprophetnet.rst",
     "xlm_roberta": "xlmroberta.rst",
     "bert_generation": "bertgeneration.rst",
+    "marian": "marian.rst",
 }
 
 # This is to make sure the transformers module imported is the one in the repo.
@@ -148,7 +149,6 @@ def get_model_doc_files():
     _ignore_modules = [
         "auto",
         "dialogpt",
-        "marian",
         "retribert",
     ]
     doc_files = []
@@ -245,6 +245,7 @@ def check_models_are_documented(module, doc_file):
 def _get_model_name(module):
     """ Get the model name for the module defining it."""
     splits = module.__name__.split("_")
+
     # Secial case for transfo_xl
     if splits[-1] == "xl":
         return "_".join(splits[-2:])