Delete fullscreen/mouselock pref data.

components/content_settings/core/browser/content_settings_default_provider.h

Index: components/content_settings/core/browser/content_settings_default_provider.h
diff --git a/components/content_settings/core/browser/content_settings_default_provider.h b/components/content_settings/core/browser/content_settings_default_provider.h
index f4f234695cac0af7bac48c25d3767bf216419226..8970258b28f892a70e997657d3ed5ad10c415aab 100644
--- a/components/content_settings/core/browser/content_settings_default_provider.h
+++ b/components/content_settings/core/browser/content_settings_default_provider.h
@@ -72,6 +72,9 @@ class DefaultProvider : public ObservableProvider {
   // Called on prefs change.
   void OnPreferenceChanged(const std::string& pref_name);
 
+  // Clean up the obsolete preferences from the user's profile.
+  void DiscardObsoletePreferences();
+
   // Copies of the pref data, so that we can read it on the IO thread.
   std::map<ContentSettingsType, std::unique_ptr<base::Value>> default_settings_;