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

chrome/browser/net/pref_proxy_config_tracker_impl.h

 // 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.
 
 #ifndef CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_IMPL_H_
 #define CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_IMPL_H_
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 12 matching lines @@
 // configuration determined by a baseline delegate ProxyConfigService on
 // non-ChromeOS platforms. ChromeOS has its own implementation of overrides in
 // chromeos::ProxyConfigServiceImpl.
 class ChromeProxyConfigService
     : public net::ProxyConfigService,
       public net::ProxyConfigService::Observer {
  public:
   // Takes ownership of the passed |base_service|.
   // If |wait_for_first_update| is true, GetLatestProxyConfig returns
   // ConfigAvailability::CONFIG_PENDING until UpdateProxyConfig has been called.
-  explicit ChromeProxyConfigService(net::ProxyConfigService* base_service,
-                                    bool wait_for_first_update);
+  ChromeProxyConfigService(net::ProxyConfigService* base_service,
+                           bool wait_for_first_update);
   virtual ~ChromeProxyConfigService();
 
   // ProxyConfigService implementation:
   virtual void AddObserver(
       net::ProxyConfigService::Observer* observer) OVERRIDE;
   virtual void RemoveObserver(
       net::ProxyConfigService::Observer* observer) OVERRIDE;
   virtual ConfigAvailability GetLatestProxyConfig(
       net::ProxyConfig* config) OVERRIDE;
   virtual void OnLazyPoll() OVERRIDE;
@@ skipping 110 matching lines @@
 
   PrefService* pref_service_;
   ChromeProxyConfigService* chrome_proxy_config_service_;  // Weak ptr.
   bool update_pending_;  // True if config has not been pushed to network stack.
   PrefChangeRegistrar proxy_prefs_;
 
   DISALLOW_COPY_AND_ASSIGN(PrefProxyConfigTrackerImpl);
 };
 
 #endif  // CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_IMPL_H_