Draft change to use base::Closure instead of PrefObserver in PrefChangeRegistrar.

chrome/browser/ui/webui/options/core_options_handler.cc

Index: chrome/browser/ui/webui/options/core_options_handler.cc
diff --git a/chrome/browser/ui/webui/options/core_options_handler.cc b/chrome/browser/ui/webui/options/core_options_handler.cc
index 8e14ea1df858665de4a9063ac193524f3063a194..a49a69becab6208dead0f985eef4e973e85fbfbc 100644
--- a/chrome/browser/ui/webui/options/core_options_handler.cc
+++ b/chrome/browser/ui/webui/options/core_options_handler.cc
@@ -206,9 +206,9 @@ void CoreOptionsHandler::ObservePref(const std::string& pref_name) {
 
 void CoreOptionsHandler::StopObservingPref(const std::string& pref_name) {
   if (g_browser_process->local_state()->FindPreference(pref_name.c_str()))
-    local_state_registrar_.Remove(pref_name.c_str(), this);
+    local_state_registrar_.Remove(pref_name.c_str());
   else
-    registrar_.Remove(pref_name.c_str(), this);
+    registrar_.Remove(pref_name.c_str());
 }
 
 void CoreOptionsHandler::SetPref(const std::string& pref_name,