Add missing (and remove superfluous) 'explicit' from constructors.

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 "base/metrics/histogram.h"
 #include "base/synchronization/lock.h"
 #include "build/build_config.h"
 #include "googleurl/src/gurl.h"
@@ skipping 206 matching lines @@
 
 NetworkChangeNotifier::NetworkChangeCalculatorParams::
     NetworkChangeCalculatorParams() {
 }
 
 // Calculates NetworkChange signal from IPAddress and ConnectionType signals.
 class NetworkChangeNotifier::NetworkChangeCalculator
     : public ConnectionTypeObserver,
       public IPAddressObserver {
  public:
-  NetworkChangeCalculator(const NetworkChangeCalculatorParams& params)
+  explicit NetworkChangeCalculator(const NetworkChangeCalculatorParams& params)
       : params_(params),
         have_announced_(false),
         last_announced_connection_type_(CONNECTION_NONE),
         pending_connection_type_(CONNECTION_NONE) {}
 
   void Init() {
     AddConnectionTypeObserver(this);
     AddIPAddressObserver(this);
   }
 
@@ skipping 318 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