Always broadcast network events to QUIC session to collect data.

Bug: 1088100, 1090018
Change-Id: Ie25ffdecabb2bbaa242379b45f28debb0b10c1fe
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2223013
Commit-Queue: Zhongyi Shi <zhongyi@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#773874}

net/quic/quic_chromium_client_session.cc

@@ -2090,9 +2090,17 @@ bool QuicChromiumClientSession::OnSendConnectivityProbingPacket(
 }
 
 void QuicChromiumClientSession::OnNetworkConnected(
-    NetworkChangeNotifier::NetworkHandle network,
-    const NetLogWithSource& net_log) {
-  DCHECK(migrate_session_on_network_change_v2_);
+    NetworkChangeNotifier::NetworkHandle network) {
+  if (connection()->IsPathDegrading()) {
+    base::TimeDelta duration =
+        tick_clock_->NowTicks() - most_recent_path_degrading_timestamp_;
+    UMA_HISTOGRAM_CUSTOM_TIMES("Net.QuicNetworkDegradingDurationTillConnected",
+                               duration, base::TimeDelta::FromMilliseconds(1),
+                               base::TimeDelta::FromMinutes(10), 50);
+  }
+  if (!migrate_session_on_network_change_v2_)
+    return;
+
   net_log_.AddEventWithInt64Params(
       NetLogEventType::QUIC_CONNECTION_MIGRATION_ON_NETWORK_CONNECTED,
       "connected_network", network);
@@ -2101,15 +2109,8 @@ void QuicChromiumClientSession::OnNetworkConnected(
   if (!wait_for_new_network_ && !connection()->IsPathDegrading())
     return;
 
-  if (connection()->IsPathDegrading()) {
-    base::TimeDelta duration =
-        tick_clock_->NowTicks() - most_recent_path_degrading_timestamp_;
-    UMA_HISTOGRAM_CUSTOM_TIMES("Net.QuicNetworkDegradingDurationTillConnected",
-                               duration, base::TimeDelta::FromMilliseconds(1),
-                               base::TimeDelta::FromMinutes(10), 50);
-
+  if (connection()->IsPathDegrading())
     current_migration_cause_ = NEW_NETWORK_CONNECTED_POST_PATH_DEGRADING;
-  }
 
   if (wait_for_new_network_) {
     wait_for_new_network_ = false;
@@ -2126,13 +2127,13 @@ void QuicChromiumClientSession::OnNetworkConnected(
 }
 
 void QuicChromiumClientSession::OnNetworkDisconnectedV2(
-    NetworkChangeNotifier::NetworkHandle disconnected_network,
-    const NetLogWithSource& migration_net_log) {
-  DCHECK(migrate_session_on_network_change_v2_);
+    NetworkChangeNotifier::NetworkHandle disconnected_network) {
+  LogMetricsOnNetworkDisconnected();
+  if (!migrate_session_on_network_change_v2_)
+    return;
   net_log_.AddEventWithInt64Params(
       NetLogEventType::QUIC_CONNECTION_MIGRATION_ON_NETWORK_DISCONNECTED,
       "disconnected_network", disconnected_network);
-  LogMetricsOnNetworkDisconnected();
 
   // Stop probing the disconnected network if there is one.
   probing_manager_.CancelProbing(disconnected_network, peer_address());

net/quic/quic_chromium_client_session.h

@@ -617,14 +617,12 @@ class NET_EXPORT_PRIVATE QuicChromiumClientSession
   // Called when NetworkChangeNotifier notifies observers of a newly
   // connected network. Migrates this session to the newly connected
   // network if the session has a pending migration.
-  void OnNetworkConnected(NetworkChangeNotifier::NetworkHandle network,
-                          const NetLogWithSource& net_log);
+  void OnNetworkConnected(NetworkChangeNotifier::NetworkHandle network);
 
   // Called when NetworkChangeNotifier broadcasts to observers of
   // |disconnected_network|.
   void OnNetworkDisconnectedV2(
-      NetworkChangeNotifier::NetworkHandle disconnected_network,
-      const NetLogWithSource& migration_net_log);
+      NetworkChangeNotifier::NetworkHandle disconnected_network);
 
   // Called when NetworkChangeNotifier broadcats to observers of a new default
   // network. Migrates this session to |new_network| if appropriate.

net/quic/quic_stream_factory.cc

@@ -1600,34 +1600,39 @@ void QuicStreamFactory::OnIPAddressChanged() {
 
 void QuicStreamFactory::OnNetworkConnected(NetworkHandle network) {
   LogPlatformNotificationInHistogram(NETWORK_CONNECTED);
-  if (!params_.migrate_sessions_on_network_change_v2)
-    return;
-
+  if (params_.migrate_sessions_on_network_change_v2) {
+    // TODO(crbug.com/1090018): clean up the scoped netlog which is no
+    // longer needed.
     ScopedConnectionMigrationEventLog scoped_event_log(net_log_,
                                                        "OnNetworkConnected");
+  }
+  // Broadcast network connected to all sessions.
+  // If migration is not turned on, session will not migrate but collect data.
   auto it = all_sessions_.begin();
   // Sessions may be deleted while iterating through the map.
   while (it != all_sessions_.end()) {
     QuicChromiumClientSession* session = it->first;
     ++it;
-    session->OnNetworkConnected(network, scoped_event_log.net_log());
+    session->OnNetworkConnected(network);
   }
 }
 
 void QuicStreamFactory::OnNetworkDisconnected(NetworkHandle network) {
   LogPlatformNotificationInHistogram(NETWORK_DISCONNECTED);
-  if (!params_.migrate_sessions_on_network_change_v2)
-    return;
-
+  if (params_.migrate_sessions_on_network_change_v2) {
+    // TODO(crbug.com/1090018): clean up the scoped netlog which is no
+    // longer needed.
     ScopedConnectionMigrationEventLog scoped_event_log(net_log_,
                                                        "OnNetworkDisconnected");
+  }
+  // Broadcast network disconnected to all sessions.
+  // If migration is not turned on, session will not migrate but collect data.
   auto it = all_sessions_.begin();
   // Sessions may be deleted while iterating through the map.
   while (it != all_sessions_.end()) {
     QuicChromiumClientSession* session = it->first;
     ++it;
-    session->OnNetworkDisconnectedV2(/*disconnected_network*/ network,
-                                     scoped_event_log.net_log());
+    session->OnNetworkDisconnectedV2(/*disconnected_network*/ network);
   }
 }
 
@@ -1652,6 +1657,8 @@ void QuicStreamFactory::OnNetworkMadeDefault(NetworkHandle network) {
 
   DCHECK_NE(NetworkChangeNotifier::kInvalidNetworkHandle, network);
   default_network_ = network;
+  // TODO(crbug.com/1090018): clean up the scoped netlog which is no
+  // longer needed.
   ScopedConnectionMigrationEventLog scoped_event_log(net_log_,
                                                      "OnNetworkMadeDefault");