Polish code

test=develop

paddle/fluid/operators/distributed_ops/fake_init_op.cc

@@ -56,8 +56,7 @@ class FakeInitOp : public framework::OperatorBase {
 
 class FakeInitOpVarTypeInference : public framework::VarTypeInference {
  public:
-  void operator()(const framework::OpDesc &op_desc,
-                  framework::BlockDesc *block) const override {}
+  void operator()(framework::InferVarTypeContext &ctx) const override {}
 };
 
 class FakeInitOpMaker : public framework::OpProtoAndCheckerMaker {