x/tools/cmd/goimports: No longer compiles on go1.4

[freeformz]

Please answer these questions before submitting your issue. Thanks!

1. What version of Go are you using (go version)?
   go1.4
2. What operating system and processor architecture are you using (go env)?
   Linux
3. What did you do?

$ go get golang.org/x/tools/cmd/goimports
package golang.org/x/tools/cmd/goimports
    imports runtime/trace: unrecognized import path "runtime/trace"

1. What did you expect to see?

$ $GOPATH/bin/goimports

1. What did you see instead?

   imports runtime/trace: unrecognized import path "runtime/trace"

Seen here: https://travis-ci.org/lib/pq/jobs/151114204

This is because of golang/tools@edf8e6f

go1.4 isn't actually supported anymore, but people do still use it, that's why lib/pq tests against it.

If there is interest in "fixing" this I can submit a CL, otherwise lib/pq will either have to remove the goimports test and/or stop testing against go1.4

[cespare]

Dup of #16434

[bradfitz]

Dup of #16434

We've decided to not fix it, since we don't test Go 1.4 ourselves at https://build.golang.org/ anymore.

[freeformz]

Sorry, I only searched open issues. :-(