cmd/vet: false positive copylocks check on len(array) and cap(array)

[valyala]

The commit bd9aa98 introduced false positive for copylocks check in `go tool vet':

var a [5]sync.Mutex

// vet incorrectly emits 'function call copies lock value: sync.Mutex' on the following lines:
n := len(a)
m := cap(a)

The commit bd9aa98 was introduced in go1.8, so this false positive should be fixed in go1.8 too.

I'll send the corresponding CL fixing this issue in a few minutes.

[valyala]

The CL is https://go-review.googlesource.com/34630 .

[gopherbot]

CL https://golang.org/cl/34630 mentions this issue.