message: Fixes 'batch_size' may be used uninitialized
  clang++-3.6: warning: 'batch_size' may be used uninitialized in this function
diff: @@ -31,7 +31,7 @@ class BatchDatasetOp : public UnaryDatasetOpKernel {
  void MakeDataset(OpKernelContext* ctx, DatasetBase* input,
  DatasetBase** output) override {
  - int64 batch_size;
  + int64 batch_size = 0;
  OP_REQUIRES_OK(ctx,
  ParseScalarArgument<int64>(ctx, "batch_size", &batch_size));
  OP_REQUIRES(
  