cmd/gopherbot: use Go 1.10, don't make vgo also Unreleased

gopherbot was setting vgo stuff to Unreleased, and then to vgo.

Change-Id: Ic97aaccf6d4db998dbb659455798b98a551714b6
Reviewed-on: https://go-review.googlesource.com/95584
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

cmd/gopherbot/Dockerfile.0

@@ -1,7 +1,7 @@
 # Copyright 2017 The Go Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
-FROM golang:1.8
+FROM golang:1.10
 LABEL maintainer "golang-dev@googlegroups.com"
 
 # BEGIN deps (run `make update-deps` to update)

cmd/gopherbot/gopherbot.go

@@ -437,11 +437,9 @@ func (b *gopherbot) setSubrepoMilestones(ctx context.Context) error {
 		if sp := strings.IndexByte(pkg, ' '); sp >= 0 {
 			pkg = pkg[:sp]
 		}
-		if strings.HasPrefix(pkg, "x/arch") {
-			return nil
-		}
 		switch pkg {
 		case "",
+			"x/arch",
 			"x/crypto/chacha20poly1305",
 			"x/crypto/curve25519",
 			"x/crypto/poly1305",
@@ -454,6 +452,9 @@ func (b *gopherbot) setSubrepoMilestones(ctx context.Context) error {
 			"x/text/width":
 			// These get vendored in. Don't mess with them.
 			return nil
+		case "x/vgo":
+			// Handled by setMiscMilestones
+			return nil
 		}
 		printIssue("subrepo-unreleased", gi)
 		if *dryRun {