New build flag system, convert Google Now flag

chrome/common/pref_names.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.
 
 // Constants for the names of various preferences, for easier changing.
 
 #ifndef CHROME_COMMON_PREF_NAMES_H_
 #define CHROME_COMMON_PREF_NAMES_H_
 
 #include <stddef.h>
 
 #include "build/build_config.h"
+#include "chrome/common/features.h"
 
 namespace prefs {
 
 // Profile prefs. Please add Local State prefs below instead.
 extern const char kChildAccountStatusKnown[];
 extern const char kDefaultApps[];
 extern const char kDisableScreenshots[];
 extern const char kForceEphemeralProfiles[];
 extern const char kHomePageIsNewTabPage[];
 extern const char kHomePage[];
@@ skipping 527 matching lines @@
 
 extern const char kWebAppCreateOnDesktop[];
 extern const char kWebAppCreateInAppsMenu[];
 extern const char kWebAppCreateInQuickLaunchBar[];
 
 extern const char kGeolocationAccessToken[];
 #if defined(OS_ANDROID)
 extern const char kGeolocationEnabled[];
 #endif
 
-#if defined(ENABLE_GOOGLE_NOW)
+#if BUILDFLAG(ENABLE_GOOGLE_NOW)
 extern const char kGoogleGeolocationAccessEnabled[];
 #endif
 extern const char kGoogleNowLauncherEnabled[];
 
 extern const char kDefaultAudioCaptureDevice[];
 extern const char kDefaultVideoCaptureDevice[];
 extern const char kMediaDeviceIdSalt[];
 
 extern const char kPrintPreviewStickySettings[];
 extern const char kCloudPrintRoot[];
@@ skipping 217 matching lines @@
 extern const char kAnimationPolicy[];
 #endif
 
 extern const char kBackgroundTracingLastUpload[];
 
 extern const char kAllowDinosaurEasterEgg[];
 
 }  // namespace prefs
 
 #endif  // CHROME_COMMON_PREF_NAMES_H_