GitLab

Mostly replaced [:x] slice operation with [:x:x]. 

According to @mdempsky, compiler specially recognizes when you combine
a pointer conversion with a full slice operation in a single expression
and makes an exception.

Updates golang/go#34972

Change-Id: I07d9de3b31da254d55f50d14c18155f8fc8f3ece
Reviewed-on: https://go-review.googlesource.com/c/go/+/203442

Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>