Add 16-bit network id to the candidate signaling.

webrtc/base/network_unittest.cc

Index: webrtc/base/network_unittest.cc
diff --git a/webrtc/base/network_unittest.cc b/webrtc/base/network_unittest.cc
index 7ad45a37afc0b7c340a256678f51a02e6bea4a87..7a26bd7ff2612a57800b351c52f5ba0b0256ded3 100644
--- a/webrtc/base/network_unittest.cc
+++ b/webrtc/base/network_unittest.cc
@@ -299,6 +299,8 @@ TEST_F(NetworkTest, TestBasicMergeNetworkList) {
   EXPECT_EQ(1U, list.size());
   EXPECT_EQ(ipv4_network1.ToString(), list[0]->ToString());
   Network* net1 = list[0];
+  uint16_t net_id1 = net1->id();
+  EXPECT_EQ(1, net_id1);
   list.clear();
 
   // Replace ipv4_network1 with ipv4_network2.
@@ -315,6 +317,9 @@ TEST_F(NetworkTest, TestBasicMergeNetworkList) {
   EXPECT_EQ(1U, list.size());
   EXPECT_EQ(ipv4_network2.ToString(), list[0]->ToString());
   Network* net2 = list[0];
+  uint16_t net_id2 = net2->id();
+  // Network id will increase.
+  EXPECT_LT(net_id1, net_id2);
   list.clear();
 
   // Add Network2 back.
@@ -332,6 +337,8 @@ TEST_F(NetworkTest, TestBasicMergeNetworkList) {
   EXPECT_EQ(2U, list.size());
   EXPECT_TRUE((net1 == list[0] && net2 == list[1]) ||
               (net1 == list[1] && net2 == list[0]));
+  EXPECT_EQ(net_id1, list[0]->id());
+  EXPECT_EQ(net_id2, list[1]->id());
   list.clear();
 
   // Call MergeNetworkList() again and verify that we don't get update
@@ -350,6 +357,8 @@ TEST_F(NetworkTest, TestBasicMergeNetworkList) {
   EXPECT_EQ(2U, list.size());
   EXPECT_TRUE((net1 == list[0] && net2 == list[1]) ||
               (net1 == list[1] && net2 == list[0]));
+  EXPECT_EQ(net_id1, list[0]->id());
+  EXPECT_EQ(net_id2, list[1]->id());
   list.clear();
 }