Formatting inconsistency with CommentGroups for declarations

[mtoader]

This:

package main

// comment

// comment

import "A"

// comment
type x a

// comment
var a int = 1

// comment
const a = iota

// comment
func a() {}

// comment
func (p *int) Length() {}

should not be formatted at all. Instead it's formatted as:

package main

// comment

// comment

import "A"

// comment

type x a

// comment

var a int = 1

// comment

const a = iota

// comment

func a() {}

// comment

func (p *int) Length() {}