net: Fix more clang warnings about missing virtual and OVERRIDE annotations.

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 "net/base/network_change_notifier_factory.h"
 #include "base/metrics/histogram.h"
 #include "build/build_config.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/net_util.h"
@@ skipping 13 matching lines @@
 // in ways that would require us to place locks around access to this object.
 // (The prohibition on global non-POD objects makes it tricky to do such a thing
 // anyway.)
 NetworkChangeNotifier* g_network_change_notifier = NULL;
 
 // Class factory singleton.
 NetworkChangeNotifierFactory* g_network_change_notifier_factory = NULL;
 
 class MockNetworkChangeNotifier : public NetworkChangeNotifier {
  public:
-  virtual ConnectionType GetCurrentConnectionType() const {
+  virtual ConnectionType GetCurrentConnectionType() const OVERRIDE {
     return CONNECTION_UNKNOWN;
   }
 };
 
 }  // namespace
 
 // The main observer class that records UMAs for network events.
 class HistogramWatcher
     : public NetworkChangeNotifier::ConnectionTypeObserver,
       public NetworkChangeNotifier::IPAddressObserver,
@@ skipping 289 matching lines @@
   DCHECK(g_network_change_notifier);
   g_network_change_notifier = NULL;
 }
 
 NetworkChangeNotifier::DisableForTest::~DisableForTest() {
   DCHECK(!g_network_change_notifier);
   g_network_change_notifier = network_change_notifier_;
 }
 
 }  // namespace net