Fix error while params_grads[1]==None
Fix error while params_grads[1]==None

PaddlePaddle/Paddle,baidu/Paddle,Canpio/Paddle,jacquesqiao/Paddle,pkuyym/Paddle,reyoung/Paddle,lcy-seso/Paddle,QiJune/Paddle,lcy-seso/Paddle,baidu/Paddle,putcn/Paddle,Canpio/Paddle,Canpio/Paddle,chengduoZH/Paddle,lcy-seso/Paddle,jacquesqiao/Paddle,luotao1/Paddle,jacquesqiao/Paddle,baidu/Paddle,tensor-tang/Paddle,lcy-seso/Paddle,putcn/Paddle,Canpio/Paddle,baidu/Paddle,jacquesqiao/Paddle,reyoung/Paddle,reyoung/Paddle,luotao1/Paddle,luotao1/Paddle,luotao1/Paddle,reyoung/Paddle,chengduoZH/Paddle,lcy-seso/Paddle,pkuyym/Paddle,tensor-tang/Paddle,pkuyym/Paddle,putcn/Paddle,reyoung/Paddle,putcn/Paddle,QiJune/Paddle,chengduoZH/Paddle,tensor-tang/Paddle,baidu/Paddle,pkuyym/Paddle,Canpio/Paddle,jacquesqiao/Paddle,lcy-seso/Paddle,QiJune/Paddle,chengduoZH/Paddle,PaddlePaddle/Paddle,PaddlePaddle/Paddle,reyoung/Paddle,tensor-tang/Paddle,QiJune/Paddle,Canpio/Paddle,PaddlePaddle/Paddle,QiJune/Paddle,jacquesqiao/Paddle,PaddlePaddle/Paddle,luotao1/Paddle,PaddlePaddle/Paddle,putcn/Paddle,tensor-tang/Paddle,QiJune/Paddle,Canpio/Paddle,chengduoZH/Paddle,luotao1/Paddle,Canpio/Paddle,pkuyym/Paddle,pkuyym/Paddle,PaddlePaddle/Paddle,luotao1/Paddle,putcn/Paddle