livelog: correct comment typo

Change-Id: Id41fb9edea46f8048cf78ba8f1afc607321c0472
Reviewed-on: https://go-review.googlesource.com/14641
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/livelog/livelog.go b/livelog/livelog.go
index 545f02a..c5b0c77 100644
--- a/livelog/livelog.go
+++ b/livelog/livelog.go
@@ -65,7 +65,7 @@
 	return append([]byte(nil), b.buf...)
 }
 
-// Bytes returns a copy of the underlying buffer as a string.
+// String returns a copy of the underlying buffer as a string.
 func (b *Buffer) String() string {
 	b.mu.Lock()
 	defer b.mu.Unlock()