net: enable multicast listener tests on solaris/illumos

It seems everything is in place for these tests to pass on solaris and
illumos, so enable them.

Fixes #7399

Change-Id: If6defb651ef9c5059c1aeccbc4fc13a12a86b682
Reviewed-on: https://go-review.googlesource.com/c/go/+/346149
Trust: Tobias Klauser <[email protected]>
Trust: Damien Neil <[email protected]>
Run-TryBot: Tobias Klauser <[email protected]>
Run-TryBot: Damien Neil <[email protected]>
TryBot-Result: Go Bot <[email protected]>
Reviewed-by: Damien Neil <[email protected]>

Author: tklauser

src/net/listen_test.go

@@ -535,8 +535,6 @@ func TestIPv4MulticastListener(t *testing.T) {
 	switch runtime.GOOS {
 	case "android", "plan9":
 		t.Skipf("not supported on %s", runtime.GOOS)
-	case "solaris", "illumos":
-		t.Skipf("not supported on solaris or illumos, see golang.org/issue/7399")
 	}
 	if !supportsIPv4() {
 		t.Skip("IPv4 is not supported")
@@ -610,8 +608,6 @@ func TestIPv6MulticastListener(t *testing.T) {
 	switch runtime.GOOS {
 	case "plan9":
 		t.Skipf("not supported on %s", runtime.GOOS)
-	case "solaris", "illumos":
-		t.Skipf("not supported on solaris or illumos, see issue 7399")
 	}
 	if !supportsIPv6() {
 		t.Skip("IPv6 is not supported")

src/net/sockoptip_stub.go

@@ -10,31 +10,25 @@ package net
 import "syscall"
 
 func setIPv4MulticastInterface(fd *netFD, ifi *Interface) error {
-	// See golang.org/issue/7399.
 	return syscall.ENOPROTOOPT
 }
 
 func setIPv4MulticastLoopback(fd *netFD, v bool) error {
-	// See golang.org/issue/7399.
 	return syscall.ENOPROTOOPT
 }
 
 func joinIPv4Group(fd *netFD, ifi *Interface, ip IP) error {
-	// See golang.org/issue/7399.
 	return syscall.ENOPROTOOPT
 }
 
 func setIPv6MulticastInterface(fd *netFD, ifi *Interface) error {
-	// See golang.org/issue/7399.
 	return syscall.ENOPROTOOPT
 }
 
 func setIPv6MulticastLoopback(fd *netFD, v bool) error {
-	// See golang.org/issue/7399.
 	return syscall.ENOPROTOOPT
 }
 
 func joinIPv6Group(fd *netFD, ifi *Interface, ip IP) error {
-	// See golang.org/issue/7399.
 	return syscall.ENOPROTOOPT
 }