Revert of Don't delete obsolete prefs in incognito

components/content_settings/core/browser/content_settings_pref_provider.cc

Index: components/content_settings/core/browser/content_settings_pref_provider.cc
diff --git a/components/content_settings/core/browser/content_settings_pref_provider.cc b/components/content_settings/core/browser/content_settings_pref_provider.cc
index 43738618351c6995cda3dc7c58269c655f3fc680..3bd173ebe0a67a91629cbf1cd2735a0a8e17feb6 100644
--- a/components/content_settings/core/browser/content_settings_pref_provider.cc
+++ b/components/content_settings/core/browser/content_settings_pref_provider.cc
@@ -197,8 +197,6 @@
 }
 
 void PrefProvider::DiscardObsoletePreferences() {
-  if (is_incognito_)
-    return;
   // These prefs were never stored on iOS/Android so they don't need to be
   // deleted.
 #if !defined(OS_IOS)