input_ids is None when evaluating
Information
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When evaluating model checkpoints, I find that input_ids passed to the model is None, but encoder_outputs are available instead. I'd like to obtain the value of input_ids, what should I do? Thanks.

To reproduce
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run the following command:

python run_summarization.py \
    --model_name_or_path facebook/bart-large \
    --do_eval \
    --dataset_name cnn_dailymail \
    --dataset_config "3.0.0" \
    --source_prefix "summarize: " \
    --output_dir /tmp/tst-summarization \
    --per_device_train_batch_size=4 \
    --per_device_eval_batch_size=4 \
    --overwrite_output_dir \
    --predict_with_generate

and print(input_ids) in the forward functions of the model.
I find that evaluating will run a bart encoder in advance, I add a self.input_ids = input_ids in the encoder, and then can obtain it easily. 