Fail DNS resolution if the result contains 127.0.53.53.

net/base/net_error_list.h

Index: net/base/net_error_list.h
diff --git a/net/base/net_error_list.h b/net/base/net_error_list.h
index 8460f6df521ff24cf45d267433bc8956cf5c453b..6f152c9ce5140161d7fc34bc9141aeae05093957 100644
--- a/net/base/net_error_list.h
+++ b/net/base/net_error_list.h
@@ -340,6 +340,12 @@ NET_ERROR(SSL_CLIENT_AUTH_CERT_BAD_FORMAT, -164)
 // minimum fallback version, and thus fallback failed.
 NET_ERROR(SSL_FALLBACK_BEYOND_MINIMUM_VERSION, -165)
 
+// Resolving a hostname to an IP address list included the IPv4 address
+// "127.0.53.53". This is a special IP address which ICANN has recommended to
+// indicate there was a name collision, and alert admins to a potential
+// problem.
+NET_ERROR(ICANN_NAME_COLLISION, -166)
+
 // Certificate error codes
 //
 // The values of certificate error codes must be consecutive.