This was the only benchmark missing the SetBytes call, as spotted
earlier by Bryan.

It's not required to make the benchmark useful, but it can still be a
good way to see how its speed is affected by the reduced allocations:

name                  time/op
CodeUnmarshal-8        12.1ms ± 1%
CodeUnmarshalReuse-8   11.4ms ± 1%

name                  speed
CodeUnmarshal-8       161MB/s ± 1%
CodeUnmarshalReuse-8  171MB/s ± 1%

name                  alloc/op
CodeUnmarshal-8        3.28MB ± 0%
CodeUnmarshalReuse-8   1.94MB ± 0%

name                  allocs/op
CodeUnmarshal-8         92.7k ± 0%
CodeUnmarshalReuse-8    77.6k ± 0%

While at it, remove some unnecessary empty lines.

Change-Id: Ib2bd92d5b3237b8f3092e8c6f863dab548fee2f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/170938
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>