encoding/base64: reduce the overflow risk when computing encode/decode length
Change-Id: I0a55cdc38ae496e2070f0b9ef317a41f82352afd
GitHub-Last-Rev:
c19527a26b0778cbb4548f49e1e365102709f068
GitHub-Pull-Request: golang/go#61407
Reviewed-on: https://go-review.googlesource.com/c/go/+/510635
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>