Remove #pragma once from content

content/browser/net/browser_online_state_observer.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 CONTENT_BROWSER_NET_BROWSER_ONLINE_STATE_OBSERVER_H_
 #define CONTENT_BROWSER_NET_BROWSER_ONLINE_STATE_OBSERVER_H_
-#pragma once
 
 #include "base/basictypes.h"
 #include "net/base/network_change_notifier.h"
 
 // Listens for changes to the online state and manages sending
 // updates to each RenderProcess via RenderProcessHost IPC.
 class BrowserOnlineStateObserver
     : public net::NetworkChangeNotifier::ConnectionTypeObserver {
  public:
   BrowserOnlineStateObserver();
   virtual ~BrowserOnlineStateObserver();
 
   // ConnectionTypeObserver implementation.
   virtual void OnConnectionTypeChanged(
       net::NetworkChangeNotifier::ConnectionType type) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(BrowserOnlineStateObserver);
 };
 
 #endif  // CONTENT_BROWSER_NET_BROWSER_ONLINE_STATE_OBSERVER_H_