Remove kNaturalScrollDefault.

chrome/browser/chromeos/preferences.cc

Index: chrome/browser/chromeos/preferences.cc
diff --git a/chrome/browser/chromeos/preferences.cc b/chrome/browser/chromeos/preferences.cc
index d3a74ff3e546361a8589ac03a67ac548ce6d9a3b..81634cab00a3b3ba1dd21d0b8f44a14dcfba2fc7 100644
--- a/chrome/browser/chromeos/preferences.cc
+++ b/chrome/browser/chromeos/preferences.cc
@@ -119,8 +119,7 @@ void Preferences::RegisterProfilePrefs(
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
   registry->RegisterBooleanPref(
       prefs::kNaturalScroll,
-      CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kNaturalScrollDefault),
+      ui::ShouldDefaultToNaturalScroll(),
       user_prefs::PrefRegistrySyncable::SYNCABLE_PRIORITY_PREF);
   registry->RegisterBooleanPref(
       prefs::kPrimaryMouseButtonRight,
@@ -565,8 +564,7 @@ void Preferences::OnIsSyncingChanged() {
 
 void Preferences::ForceNaturalScrollDefault() {
   DVLOG(1) << "ForceNaturalScrollDefault";
-  if (CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kNaturalScrollDefault) &&
+  if (ui::ShouldDefaultToNaturalScroll() &&
       prefs_->IsSyncing() &&
       !prefs_->GetUserPrefValue(prefs::kNaturalScroll)) {
     DVLOG(1) << "Natural scroll forced to true";