Revert "Faster decorator"

[lixinqi]

Reverts #5996

[github-actions]

Speed stats:

GPU Name: GeForce GTX 1080 

PyTorch resnet50 time: 141.9ms (= 7092.9ms / 50, input_shape=[16, 3, 224, 224], backward is enabled)
OneFlow resnet50 time: 129.0ms (= 6451.6ms / 50, input_shape=[16, 3, 224, 224], backward is enabled)
Relative speed: 1.10 (= 141.9ms / 129.0ms)

PyTorch resnet50 time: 87.0ms (= 4352.0ms / 50, input_shape=[8, 3, 224, 224], backward is enabled)
OneFlow resnet50 time: 74.9ms (= 3742.5ms / 50, input_shape=[8, 3, 224, 224], backward is enabled)
Relative speed: 1.16 (= 87.0ms / 74.9ms)

PyTorch resnet50 time: 58.4ms (= 2918.2ms / 50, input_shape=[4, 3, 224, 224], backward is enabled)
OneFlow resnet50 time: 47.5ms (= 2374.8ms / 50, input_shape=[4, 3, 224, 224], backward is enabled)
Relative speed: 1.23 (= 58.4ms / 47.5ms)

PyTorch resnet50 time: 46.0ms (= 2300.7ms / 50, input_shape=[2, 3, 224, 224], backward is enabled)
OneFlow resnet50 time: 38.5ms (= 1923.5ms / 50, input_shape=[2, 3, 224, 224], backward is enabled)
Relative speed: 1.20 (= 46.0ms / 38.5ms)

PyTorch resnet50 time: 43.1ms (= 2153.9ms / 50, input_shape=[1, 3, 224, 224], backward is enabled)
OneFlow resnet50 time: 33.3ms (= 1667.3ms / 50, input_shape=[1, 3, 224, 224], backward is enabled)
Relative speed: 1.29 (= 43.1ms / 33.3ms)