Fix "defined but not used" build error when enable_webrtc=false.

chrome/browser/renderer_preferences_util.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 "chrome/browser/renderer_preferences_util.h"
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 18 matching lines @@
 #if defined(OS_MACOSX)
 #include "ui/base/cocoa/defaults_utils.h"
 #endif
 
 #if defined(USE_AURA) && defined(OS_LINUX) && !defined(OS_CHROMEOS)
 #include "chrome/browser/themes/theme_service.h"
 #include "chrome/browser/themes/theme_service_factory.h"
 #include "ui/views/linux_ui/linux_ui.h"
 #endif
 
+#if defined(ENABLE_WEBRTC)
 namespace {
 
 // Parses a string |range| with a port range in the form "<min>-<max>".
 // If |range| is not in the correct format or contains an invalid range, zero
 // is written to |min_port| and |max_port|.
 // TODO(guidou): Consider replacing with remoting/protocol/port_range.cc
 void ParsePortRange(const std::string& range,
                     uint16_t* min_port,
                     uint16_t* max_port) {
   *min_port = 0;
@@ skipping 19 matching lines @@
   if (min_port_uint == 0 || min_port_uint > max_port_uint ||
       max_port_uint > UINT16_MAX) {
     return;
   }
 
   *min_port = static_cast<uint16_t>(min_port_uint);
   *max_port = static_cast<uint16_t>(max_port_uint);
 }
 
 }  // namespace
+#endif
 
 namespace renderer_preferences_util {
 
 void UpdateFromSystemSettings(content::RendererPreferences* prefs,
                               Profile* profile,
                               content::WebContents* web_contents) {
   const PrefService* pref_service = profile->GetPrefs();
   prefs->accept_languages = pref_service->GetString(prefs::kAcceptLanguages);
   prefs->enable_referrers = pref_service->GetBoolean(prefs::kEnableReferrers);
   prefs->enable_do_not_track =
@@ skipping 75 matching lines @@
   prefs->subpixel_rendering = params.subpixel_rendering;
 #endif
 
 #if !defined(OS_MACOSX)
   prefs->plugin_fullscreen_allowed =
       pref_service->GetBoolean(prefs::kFullscreenAllowed);
 #endif
 }
 
 }  // namespace renderer_preferences_util