Relanding Generate localhost candidate when no STUN/TURN and portallocator has the right flag spefi…

webrtc/base/ipaddress.cc

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 480 matching lines @@
     } else if (IPIsV4Compatibility(ip) || IPIsSiteLocal(ip) || IPIs6Bone(ip)) {
       return 1;
     } else {
       // A 'normal' IPv6 address.
       return 40;
     }
   }
   return 0;
 }
 
-}  // Namespace talk base
+IPAddress GetLoopbackIP(int family) {
+  if (family == AF_INET) {
+    return rtc::IPAddress(INADDR_LOOPBACK);
+  }
+  if (family == AF_INET6) {
+    return rtc::IPAddress(in6addr_loopback);
+  }
+  return rtc::IPAddress();
+}
+}  // Namespace rtc