Bug 1434531 - fix missing TCP relay candidates. r=drno

Because the nr_transport_addr_check_compatibility check also includes
protocol, it was failing checks that used to pass.  However, the actual
address used was created farther down in code by copying the current
address and setting the protocol to TCP.  Moving that address copy up
in the processing flow lets the more stringent check work.

MozReview-Commit-ID: 95SOQzxuxXB

--HG--
extra : rebase_source : 95f4cf6d9f10ee4f81c56d7bbe8027c46749cfb8

src/ice/ice_component.c

@@ -581,9 +581,14 @@ static int nr_ice_component_initialize_tcp(struct nr_ice_ctx_ *ctx,nr_ice_compon
         if (ctx->turn_servers[j].turn_server.transport != IPPROTO_TCP)
           continue;
 
+        /* Create relay candidate */
+        if ((r=nr_transport_addr_copy(&addr, &addrs[i].addr)))
+          ABORT(r);
+        addr.protocol = IPPROTO_TCP;
+
         if (ctx->turn_servers[j].turn_server.type == NR_ICE_STUN_SERVER_TYPE_ADDR) {
           if (nr_transport_addr_check_compatibility(
-                &addrs[i].addr,
+                &addr,
                 &ctx->turn_servers[j].turn_server.u.addr)) {
             r_log(LOG_ICE,LOG_INFO,"ICE(%s): Skipping TURN server because of link local mis-match",ctx->label);
             continue;
@@ -613,11 +618,6 @@ static int nr_ice_component_initialize_tcp(struct nr_ice_ctx_ *ctx,nr_ice_compon
           }
         }
 
-        /* Create relay candidate */
-        if ((r=nr_transport_addr_copy(&addr, &addrs[i].addr)))
-          ABORT(r);
-        addr.protocol = IPPROTO_TCP;
-
         /* If we're going to use TLS, make sure that's recorded */
         if (ctx->turn_servers[j].turn_server.tls) {
           strncpy(addr.tls_host,