Move enable extensions define to a build flag.

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index 30e94ffe5b9bda171180c79007767e448787cb23..6a7249dd3af0fbc0969acda7f36eadd82e8923cd 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -8,6 +8,7 @@
 #include "build/build_config.h"
 #include "chrome/common/features.h"
 #include "chrome/common/pref_font_webkit_names.h"
+#include "extensions/features/features.h"
 
 namespace prefs {
 
@@ -1269,7 +1270,7 @@ const char kEasyUnlockPairing[] = "easy_unlock.pairing";
 // in order to use Easy Unlock.
 const char kEasyUnlockProximityRequired[] = "easy_unlock.proximity_required";
 
-#if defined(ENABLE_EXTENSIONS)
+#if BUILDFLAG(ENABLE_EXTENSIONS)
 // Used to indicate whether or not the toolbar redesign bubble has been shown
 // and acknowledged, and the last time the bubble was shown.
 const char kToolbarIconSurfacingBubbleAcknowledged[] =
@@ -2252,7 +2253,7 @@ const char kRecoveryComponentNeedsElevation[] =
 const char kRegisteredSupervisedUserWhitelists[] =
     "supervised_users.whitelists";
 
-#if defined(ENABLE_EXTENSIONS)
+#if BUILDFLAG(ENABLE_EXTENSIONS)
 // Policy that indicates how to handle animated images.
 const char kAnimationPolicy[] = "settings.a11y.animation_policy";
 #endif