Move enable extensions define to a build flag.

chrome/browser/net/chrome_extensions_network_delegate.h

 // Copyright 2014 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_CHROME_EXTENSIONS_NETWORK_DELEGATE_H_
 #define CHROME_BROWSER_NET_CHROME_EXTENSIONS_NETWORK_DELEGATE_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
+#include "extensions/features/features.h"
 #include "net/base/network_delegate_impl.h"
 
 namespace extensions {
 class EventRouterForwarder;
 class InfoMap;
 }
 
 // ChromeExtensionsNetworkDelegate is the extensions-only portion of
 // ChromeNetworkDelegate. When extensions are disabled, do nothing.
 class ChromeExtensionsNetworkDelegate : public net::NetworkDelegateImpl {
@@ skipping 49 matching lines @@
       net::URLRequest* request,
       const net::AuthChallengeInfo& auth_info,
       const AuthCallback& callback,
       net::AuthCredentials* credentials) override;
 
  protected:
   ChromeExtensionsNetworkDelegate();
 
   void* profile_;
 
-#if defined(ENABLE_EXTENSIONS)
+#if BUILDFLAG(ENABLE_EXTENSIONS)
   scoped_refptr<extensions::InfoMap> extension_info_map_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(ChromeExtensionsNetworkDelegate);
 };
 
 #endif  // CHROME_BROWSER_NET_CHROME_EXTENSIONS_NETWORK_DELEGATE_H_