Add configuration for port migration via "allow_port_migration" for desktop.

Note this change also removes server migration configuration path on desktop.
This feature has been minimally tested on a local machine, see more metials
in the associated bug.

Bug: 999285
Change-Id: Iffb2fc6c1b02bedaf91491a2f1831d3a43ca6cbd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1820042
Auto-Submit: Zhongyi Shi <zhongyi@chromium.org>
Reviewed-by: Ryan Hamilton <rch@chromium.org>
Commit-Queue: Ryan Hamilton <rch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#699352}

components/network_session_configurator/browser/network_session_configurator.cc

@@ -321,6 +321,12 @@ bool ShouldQuicMigrateSessionsEarlyV2(
       "true");
 }
 
+bool ShouldQuicAllowPortMigration(
+    const VariationParameters& quic_trial_params) {
+  return base::LowerCaseEqualsASCII(
+      GetVariationParam(quic_trial_params, "allow_port_migration"), "true");
+}
+
 bool ShouldQuicRetryOnAlternateNetworkBeforeHandshake(
     const VariationParameters& quic_trial_params) {
   return base::LowerCaseEqualsASCII(
@@ -404,12 +410,6 @@ int GetQuicMaxNumMigrationsToNonDefaultNetworkOnPathDegrading(
   return 0;
 }
 
-bool ShouldQuicAllowServerMigration(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "allow_server_migration"), "true");
-}
-
 int GetQuicInitialRttForHandshakeMilliseconds(
     const VariationParameters& quic_trial_params) {
   int value;
@@ -533,6 +533,8 @@ void ConfigureQuicParams(base::StringPiece quic_trial_group,
         ShouldQuicMigrateSessionsOnNetworkChangeV2(quic_trial_params);
     params->quic_params.migrate_sessions_early_v2 =
         ShouldQuicMigrateSessionsEarlyV2(quic_trial_params);
+    params->quic_params.allow_port_migration =
+        ShouldQuicAllowPortMigration(quic_trial_params);
     params->quic_params.retry_on_alternate_network_before_handshake =
         ShouldQuicRetryOnAlternateNetworkBeforeHandshake(quic_trial_params);
     params->quic_params.go_away_on_path_degrading =
@@ -580,8 +582,6 @@ void ConfigureQuicParams(base::StringPiece quic_trial_group,
           .max_migrations_to_non_default_network_on_path_degrading =
           max_migrations_to_non_default_network_on_path_degrading;
     }
-    params->quic_params.allow_server_migration =
-        ShouldQuicAllowServerMigration(quic_trial_params);
     params->quic_host_allowlist = GetQuicHostAllowlist(quic_trial_params);
 
     SetQuicFlags(quic_trial_params);

components/network_session_configurator/browser/network_session_configurator_unittest.cc

@@ -458,15 +458,15 @@ TEST_F(
 }
 
 TEST_F(NetworkSessionConfiguratorTest,
-       QuicAllowServerMigrationFromFieldTrialParams) {
+       QuicAllowPortMigrationFromFieldTrialParams) {
   std::map<std::string, std::string> field_trial_params;
-  field_trial_params["allow_server_migration"] = "true";
+  field_trial_params["allow_port_migration"] = "true";
   variations::AssociateVariationParams("QUIC", "Enabled", field_trial_params);
   base::FieldTrialList::CreateFieldTrial("QUIC", "Enabled");
 
   ParseFieldTrials();
 
-  EXPECT_TRUE(params_.quic_params.allow_server_migration);
+  EXPECT_TRUE(params_.quic_params.allow_port_migration);
 }
 
 TEST_F(NetworkSessionConfiguratorTest, PacketLengthFromFieldTrialParams) {