Model Weights Fail to Load from Pre-Trained Model when Using `tf.name_scope` 
Author: EhsanM4t1qbit
Pull request: no

## Environment info
<!-- You can run the command `transformers-cli env` and copy-and-paste its output below.
     Don't forget to fill out the missing fields in that output! -->

- `transformers` version: 4.3.0
- Platform: Darwin-19.2.0-x86_64-i386-64bit
- Python version: 3.6.6
- PyTorch version (GPU?): 1.7.1 (False)
- Tensorflow version (GPU?): 2.3.1 (False)
- Using GPU in script?: No
- Using distributed or parallel set-up in script?: No

@LysandreJik @jplu

I can't load the pre-trained weights from BERT or Roberta when using a `tf.name_scope`.
Without defining a name scope, the code runs as expected.
```
text_model= TFBertModel.from_pretrained('bert-base-uncased')    
Some layers from the model checkpoint at bert-base-uncased were not used when initializing TFBertModel: ['nsp___cls', 'mlm___cls']
- This IS expected if you are initializing TFBertModel from the checkpoint of a model trained on another task or with another architecture (e.g. initializing a BertForSequenceClassification model from a BertForPreTraining model).
- This IS NOT expected if you are initializing TFBertModel from the checkpoint of a model that you expect to be exactly identical (initializing a BertForSequenceClassification model from a BertForSequenceClassification model).
All the layers of TFBertModel were initialized from the model checkpoint at bert-base-uncased.
If your task is similar to the task the model of the checkpoint was trained on, you can already use TFBertModel for predictions without further training.

```
By adding a name_scope, however, I'll get a warning, indicating that the pre-trained weights are not loaded.
```
import tensorflow as tf
from transformers import TFBertModel
with tf.name_scope("Model"):
    text_model_2 = TFBertModel.from_pretrained('bert-base-uncased')
Some layers from the model checkpoint at bert-base-uncased were not used when initializing TFBertModel: ['nsp___cls', 'mlm___cls', 'bert/encoder/layer_._2/attention/self/key/bias:0', 'bert/encoder/layer_._7/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._4/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._6/attention/output/dense/kernel:0', 'bert/encoder/layer_._9/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._6/attention/self/key/bias:0', 'bert/encoder/layer_._5/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._3/output/LayerNorm/gamma:0', 'bert/encoder/layer_._5/attention/self/value/kernel:0', 'bert/encoder/layer_._9/attention/self/key/bias:0', 'bert/encoder/layer_._6/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._7/intermediate/dense/bias:0', 'bert/encoder/layer_._4/attention/self/value/kernel:0', 'bert/encoder/layer_._11/attention/self/key/bias:0', 'bert/encoder/layer_._5/attention/self/key/bias:0', 'bert/encoder/layer_._4/attention/self/query/bias:0', 'bert/encoder/layer_._7/output/dense/kernel:0', 'bert/encoder/layer_._8/output/dense/bias:0', 'bert/encoder/layer_._8/intermediate/dense/bias:0', 'bert/encoder/layer_._9/output/LayerNorm/gamma:0', 'bert/encoder/layer_._2/attention/self/key/kernel:0', 'bert/encoder/layer_._0/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._1/intermediate/dense/bias:0', 'bert/encoder/layer_._4/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._1/attention/self/key/kernel:0', 'bert/encoder/layer_._1/attention/self/query/kernel:0', 'bert/encoder/layer_._1/attention/output/dense/bias:0', 'bert/encoder/layer_._6/output/dense/kernel:0', 'bert/encoder/layer_._8/attention/self/key/kernel:0', 'bert/encoder/layer_._8/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._5/output/LayerNorm/beta:0', 'bert/encoder/layer_._1/attention/self/value/bias:0', 'bert/encoder/layer_._11/output/dense/kernel:0', 'bert/encoder/layer_._8/attention/output/dense/bias:0', 'bert/encoder/layer_._6/intermediate/dense/kernel:0', 'bert/encoder/layer_._8/attention/self/value/kernel:0', 'bert/encoder/layer_._7/attention/self/value/kernel:0', 'bert/encoder/layer_._11/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._5/attention/self/value/bias:0', 'bert/encoder/layer_._9/attention/output/dense/kernel:0', 'bert/encoder/layer_._1/attention/self/key/bias:0', 'bert/encoder/layer_._4/attention/output/dense/bias:0', 'bert/encoder/layer_._1/intermediate/dense/kernel:0', 'bert/encoder/layer_._6/output/LayerNorm/gamma:0', 'bert/encoder/layer_._2/intermediate/dense/kernel:0', 'bert/encoder/layer_._4/attention/self/query/kernel:0', 'bert/encoder/layer_._4/output/LayerNorm/gamma:0', 'bert/encoder/layer_._0/attention/self/query/bias:0', 'bert/encoder/layer_._11/attention/output/dense/bias:0', 'bert/encoder/layer_._2/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._10/attention/self/value/bias:0', 'bert/encoder/layer_._2/intermediate/dense/bias:0', 'bert/encoder/layer_._9/output/LayerNorm/beta:0', 'bert/encoder/layer_._0/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._3/attention/output/dense/bias:0', 'bert/encoder/layer_._2/attention/self/value/kernel:0', 'bert/encoder/layer_._3/output/dense/kernel:0', 'bert/encoder/layer_._1/attention/self/query/bias:0', 'bert/encoder/layer_._6/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._10/attention/output/dense/kernel:0', 'bert/encoder/layer_._3/intermediate/dense/kernel:0', 'bert/encoder/layer_._4/output/dense/kernel:0', 'bert/encoder/layer_._6/attention/self/key/kernel:0', 'bert/encoder/layer_._0/output/LayerNorm/beta:0', 'bert/encoder/layer_._7/attention/self/query/kernel:0', 'bert/encoder/layer_._1/output/dense/kernel:0', 'bert/encoder/layer_._0/output/dense/bias:0', 'bert/encoder/layer_._8/attention/output/dense/kernel:0', 'bert/encoder/layer_._11/attention/self/query/kernel:0', 'bert/encoder/layer_._9/attention/self/value/kernel:0', 'bert/encoder/layer_._2/attention/self/query/kernel:0', 'bert/encoder/layer_._4/intermediate/dense/bias:0', 'bert/encoder/layer_._4/intermediate/dense/kernel:0', 'bert/encoder/layer_._0/attention/self/key/kernel:0', 'bert/encoder/layer_._8/attention/self/query/bias:0', 'bert/encoder/layer_._5/attention/output/dense/bias:0', 'bert/encoder/layer_._10/attention/output/dense/bias:0', 'bert/encoder/layer_._11/attention/self/key/kernel:0', 'bert/encoder/layer_._2/output/LayerNorm/gamma:0', 'bert/encoder/layer_._10/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._3/attention/self/query/kernel:0', 'bert/encoder/layer_._10/intermediate/dense/kernel:0', 'bert/encoder/layer_._10/attention/self/query/bias:0', 'bert/encoder/layer_._7/output/LayerNorm/beta:0', 'bert/encoder/layer_._6/intermediate/dense/bias:0', 'bert/encoder/layer_._3/attention/self/key/kernel:0', 'bert/encoder/layer_._8/intermediate/dense/kernel:0', 'bert/encoder/layer_._5/intermediate/dense/kernel:0', 'bert/encoder/layer_._6/output/dense/bias:0', 'bert/encoder/layer_._0/attention/self/query/kernel:0', 'bert/encoder/layer_._6/attention/self/query/bias:0', 'bert/encoder/layer_._7/attention/output/dense/kernel:0', 'bert/encoder/layer_._8/output/LayerNorm/beta:0', 'bert/encoder/layer_._9/attention/self/query/bias:0', 'bert/encoder/layer_._3/output/dense/bias:0', 'bert/encoder/layer_._11/intermediate/dense/bias:0', 'bert/encoder/layer_._4/attention/output/dense/kernel:0', 'bert/encoder/layer_._6/output/LayerNorm/beta:0', 'bert/encoder/layer_._5/output/dense/kernel:0', 'bert/encoder/layer_._3/attention/self/value/kernel:0', 'bert/encoder/layer_._8/output/LayerNorm/gamma:0', 'bert/encoder/layer_._1/attention/output/dense/kernel:0', 'bert/encoder/layer_._11/output/dense/bias:0', 'bert/encoder/layer_._0/output/LayerNorm/gamma:0', 'bert/encoder/layer_._10/output/LayerNorm/beta:0', 'bert/encoder/layer_._0/intermediate/dense/bias:0', 'bert/encoder/layer_._9/output/dense/bias:0', 'bert/encoder/layer_._2/attention/self/value/bias:0', 'bert/encoder/layer_._5/output/LayerNorm/gamma:0', 'bert/encoder/layer_._1/output/dense/bias:0', 'bert/encoder/layer_._0/attention/self/value/kernel:0', 'bert/encoder/layer_._7/attention/output/dense/bias:0', 'bert/encoder/layer_._10/output/dense/bias:0', 'bert/encoder/layer_._11/attention/self/value/kernel:0', 'bert/encoder/layer_._3/intermediate/dense/bias:0', 'bert/encoder/layer_._8/attention/self/query/kernel:0', 'bert/encoder/layer_._10/intermediate/dense/bias:0', 'bert/encoder/layer_._6/attention/self/value/kernel:0', 'bert/encoder/layer_._5/attention/output/dense/kernel:0', 'bert/encoder/layer_._9/intermediate/dense/kernel:0', 'bert/encoder/layer_._4/attention/self/value/bias:0', 'bert/encoder/layer_._4/output/dense/bias:0', 'bert/encoder/layer_._5/attention/output/LayerNorm/beta:0', 'bert/embeddings/LayerNorm/gamma:0', 'bert/embeddings/position_embeddings/embeddings:0', 'bert/encoder/layer_._4/attention/self/key/kernel:0', 'bert/encoder/layer_._7/attention/self/query/bias:0', 'bert/encoder/layer_._10/attention/self/query/kernel:0', 'bert/encoder/layer_._10/attention/self/key/kernel:0', 'bert/encoder/layer_._11/attention/self/value/bias:0', 'bert/encoder/layer_._2/attention/self/query/bias:0', 'bert/encoder/layer_._4/attention/self/key/bias:0', 'bert/encoder/layer_._7/attention/self/key/kernel:0', 'bert/encoder/layer_._11/intermediate/dense/kernel:0', 'bert/encoder/layer_._3/attention/self/value/bias:0', 'bert/pooler/dense/kernel:0', 'bert/encoder/layer_._2/output/dense/bias:0', 'bert/encoder/layer_._7/intermediate/dense/kernel:0', 'bert/encoder/layer_._8/attention/self/key/bias:0', 'bert/embeddings/word_embeddings/weight:0', 'bert/encoder/layer_._11/output/LayerNorm/beta:0', 'bert/encoder/layer_._9/attention/self/value/bias:0', 'bert/embeddings/token_type_embeddings/embeddings:0', 'bert/encoder/layer_._1/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._6/attention/self/value/bias:0', 'bert/pooler/dense/bias:0', 'bert/encoder/layer_._8/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._1/output/LayerNorm/gamma:0', 'bert/encoder/layer_._9/intermediate/dense/bias:0', 'bert/encoder/layer_._1/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._9/output/dense/kernel:0', 'bert/encoder/layer_._0/output/dense/kernel:0', 'bert/encoder/layer_._3/output/LayerNorm/beta:0', 'bert/encoder/layer_._7/output/LayerNorm/gamma:0', 'bert/encoder/layer_._11/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._3/attention/output/dense/kernel:0', 'bert/encoder/layer_._3/attention/self/key/bias:0', 'bert/encoder/layer_._10/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._2/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._6/attention/output/dense/bias:0', 'bert/encoder/layer_._7/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._0/intermediate/dense/kernel:0', 'bert/encoder/layer_._10/attention/self/value/kernel:0', 'bert/encoder/layer_._5/attention/self/key/kernel:0', 'bert/encoder/layer_._10/attention/self/key/bias:0', 'bert/encoder/layer_._9/attention/self/key/kernel:0', 'bert/encoder/layer_._1/attention/self/value/kernel:0', 'bert/encoder/layer_._7/output/dense/bias:0', 'bert/encoder/layer_._11/output/LayerNorm/gamma:0', 'bert/encoder/layer_._0/attention/self/key/bias:0', 'bert/encoder/layer_._3/attention/output/LayerNorm/beta:0', 'bert/encoder/layer_._11/attention/output/dense/kernel:0', 'bert/encoder/layer_._7/attention/self/key/bias:0', 'bert/encoder/layer_._3/attention/output/LayerNorm/gamma:0', 'bert/encoder/layer_._10/output/dense/kernel:0', 'bert/encoder/layer_._10/output/LayerNorm/gamma:0', 'bert/encoder/layer_._5/output/dense/bias:0', 'bert/encoder/layer_._9/attention/output/dense/bias:0', 'bert/encoder/layer_._11/attention/self/query/bias:0', 'bert/encoder/layer_._2/output/LayerNorm/beta:0', 'bert/encoder/layer_._7/attention/self/value/bias:0', 'bert/encoder/layer_._1/output/LayerNorm/beta:0', 'bert/encoder/layer_._5/intermediate/dense/bias:0', 'bert/embeddings/LayerNorm/beta:0', 'bert/encoder/layer_._9/attention/self/query/kernel:0', 'bert/encoder/layer_._2/output/dense/kernel:0', 'bert/encoder/layer_._0/attention/output/dense/kernel:0', 'bert/encoder/layer_._2/attention/output/dense/bias:0', 'bert/encoder/layer_._4/output/LayerNorm/beta:0', 'bert/encoder/layer_._0/attention/self/value/bias:0', 'bert/encoder/layer_._8/output/dense/kernel:0', 'bert/encoder/layer_._2/attention/output/dense/kernel:0', 'bert/encoder/layer_._6/attention/self/query/kernel:0', 'bert/encoder/layer_._0/attention/output/dense/bias:0', 'bert/encoder/layer_._3/attention/self/query/bias:0', 'bert/encoder/layer_._5/attention/self/query/bias:0', 'bert/encoder/layer_._5/attention/self/query/kernel:0', 'bert/encoder/layer_._8/attention/self/value/bias:0', 'bert/encoder/layer_._9/attention/output/LayerNorm/gamma:0']
- This IS expected if you are initializing TFBertModel from the checkpoint of a model trained on another task or with another architecture (e.g. initializing a BertForSequenceClassification model from a BertForPreTraining model).
- This IS NOT expected if you are initializing TFBertModel from the checkpoint of a model that you expect to be exactly identical (initializing a BertForSequenceClassification model from a BertForSequenceClassification model).
All the layers of TFBertModel were initialized from the model checkpoint at bert-base-uncased.
If your task is similar to the task the model of the checkpoint was trained on, you can already use TFBertModel for predictions without further training.
```
The problem I think is rooted in https://github.com/huggingface/transformers/blob/master/src/transformers/modeling_tf_utils.py#L487. 

Comments:
Hello!

You cannot load a model inside a namescope. This is the expected behavior because all the names are forced insides the h5 file. To use the model you have to load it outside your defined namescope and then use it inside.

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/master/CONTRIBUTING.md) are likely to be ignored.