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

chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc

Index: chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc b/chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc
index 0d2a56388c2beb000374f0a267d14e0167a64999..007958a52f2a2b12a6e4d2e369b0e18c7459d965 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc
@@ -842,7 +842,7 @@ void ChromeLauncherController::PersistPinnedState() {
   // Mutating kPinnedLauncherApps is going to notify us and trigger us to
   // process the change. We don't want that to happen so remove ourselves as a
   // listener.
-  pref_change_registrar_.Remove(prefs::kPinnedLauncherApps, this);
+  pref_change_registrar_.Remove(prefs::kPinnedLauncherApps);
   {
     ListPrefUpdate updater(profile_->GetPrefs(), prefs::kPinnedLauncherApps);
     updater->Clear();