Allow IP migration.

net/quic/core/quic_utils.cc

Index: net/quic/core/quic_utils.cc
diff --git a/net/quic/core/quic_utils.cc b/net/quic/core/quic_utils.cc
index efc5b5dd3fbc1fe8aeb94fbf6e1b8949194cbc13..52c0def6a0d85e390ff635cdbe9e3419084af20d 100644
--- a/net/quic/core/quic_utils.cc
+++ b/net/quic/core/quic_utils.cc
@@ -390,7 +390,7 @@ string QuicUtils::PeerAddressChangeTypeToString(PeerAddressChangeType type) {
     RETURN_STRING_LITERAL(IPV4_TO_IPV6_CHANGE);
     RETURN_STRING_LITERAL(IPV6_TO_IPV4_CHANGE);
     RETURN_STRING_LITERAL(IPV6_TO_IPV6_CHANGE);
-    RETURN_STRING_LITERAL(UNSPECIFIED_CHANGE);
+    RETURN_STRING_LITERAL(IPV4_TO_IPV4_CHANGE);
   }
   return "INVALID_PEER_ADDRESS_CHANGE_TYPE";
 }
@@ -513,7 +513,7 @@ PeerAddressChangeType QuicUtils::DetermineAddressChangeType(
     return IPV4_SUBNET_CHANGE;
   }
 
-  return UNSPECIFIED_CHANGE;
+  return IPV4_TO_IPV4_CHANGE;
 }
 
 string QuicUtils::HexEncode(const char* data, size_t length) {