fixed unexpected reflect behavior

After tls.Unmarshal() an empty slice is not assigned the nil value, but rather
a slice of zero length.  It is in contrast to NewTreeHeadV1(), which assigns a
nil value.  Therefore, reflect.DeepEqual() considers them to be different.

Fixed by assigning an empty tree head extension as `make([]byte, 0)`,
and not looking for nil values but rather zero-length values with len().

Further read: "Note that a non-nil empty slice and a nil slice [...] are
not deeply equal." (https://golang.org/pkg/reflect/#DeepEqual).

0 files changed, 0 insertions, 0 deletions