Add the sparse feature information during logging in sparse lookup layer (#24863)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/24863
Add the sparse feature name in logging for ease of debugging
Test Plan:
./buck-out/gen/caffe2/caffe2/fb/dper/layer_models/sparse_nn/pooling_test#binary.par -r test_simple_sum_pooling_named_exception
Another test for id_score_list. the original sparse_key is equivalent to get_key(self.input_record)()
P98343716
./buck-out/gen/caffe2/caffe2/python/layers_test-2.7#binary.par -r test_get_key
Reviewed By: chocjy
Differential Revision: D16901964
fbshipit-source-id: 2523de2e290aca20afd0b909111541d3d152a588
