Expire but don't clear HostCache on DNS config change

net/base/network_change_notifier.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/base/network_change_notifier.h"
 
 #include <limits>
 #include <unordered_set>
 
 #include "base/macros.h"
@@ skipping 912 matching lines @@
 }
 
 // static
 void NetworkChangeNotifier::NotifyObserversOfConnectionTypeChangeForTests(
     ConnectionType type) {
   if (g_network_change_notifier)
     g_network_change_notifier->NotifyObserversOfConnectionTypeChangeImpl(type);
 }
 
 // static
+void NetworkChangeNotifier::NotifyObserversOfDNSChangeForTests() {
+  if (g_network_change_notifier)
+    g_network_change_notifier->NotifyObserversOfDNSChangeImpl();
+}
+
+// static
 void NetworkChangeNotifier::NotifyObserversOfNetworkChangeForTests(
     ConnectionType type) {
   if (g_network_change_notifier)
     g_network_change_notifier->NotifyObserversOfNetworkChangeImpl(type);
 }
 
 // static
 void NetworkChangeNotifier::NotifyObserversOfInitialDNSConfigReadForTests() {
   if (g_network_change_notifier)
     g_network_change_notifier->NotifyObserversOfInitialDNSConfigReadImpl();
@@ skipping 239 matching lines @@
 
 NetworkChangeNotifier::DisableForTest::~DisableForTest() {
   DCHECK(!g_network_change_notifier);
   g_network_change_notifier = network_change_notifier_;
 }
 
 void NetworkChangeNotifier::DNSObserver::OnInitialDNSConfigRead() {
 }
 
 }  // namespace net