[MD settings] lighter weight initializer for protocol handler enabled messages

chrome/browser/ui/webui/settings/protocol_handlers_handler.h

Index: chrome/browser/ui/webui/settings/protocol_handlers_handler.h
diff --git a/chrome/browser/ui/webui/settings/protocol_handlers_handler.h b/chrome/browser/ui/webui/settings/protocol_handlers_handler.h
index 89115348b3aa4b9d0ac414ee0eccc6f830e1a399..89ec318c344a86fcf7d0ed73a7bc61029aa10cfb 100644
--- a/chrome/browser/ui/webui/settings/protocol_handlers_handler.h
+++ b/chrome/browser/ui/webui/settings/protocol_handlers_handler.h
@@ -44,9 +44,15 @@ class ProtocolHandlersHandler : public SettingsPageUIHandler,
                const content::NotificationDetails& details) override;
 
  private:
-  // Called to fetch the initial list of data to show.
+  // Called to fetch the initial list of data to show. If the full list of
+  // handlers is not needed, consider using HandleInitializeUpdates instead.
   void HandleInitializeList(const base::ListValue* args);
 
+  // Called to begin updates to the handlers enabled status. This is a subset
+  // (lighter alternative) of HandleInitializeList. There's no need to call this
+  // function if HandleInitializeList is called.
+  void HandleInitializeUpdates(const base::ListValue* args);
+
   // Notifies the JS side whether the handlers are enabled or not.
   void SendHandlersEnabledValue();