Remove PrefObserver usage, batch 9.

chrome/browser/printing/cloud_print/cloud_print_proxy_service.cc

Index: chrome/browser/printing/cloud_print/cloud_print_proxy_service.cc
diff --git a/chrome/browser/printing/cloud_print/cloud_print_proxy_service.cc b/chrome/browser/printing/cloud_print/cloud_print_proxy_service.cc
index 18ed40dfa27f60df8c1bf8dff464806f4e87aae2..cf16173485d3ef21574544c5feac59afd0d6239d 100644
--- a/chrome/browser/printing/cloud_print/cloud_print_proxy_service.cc
+++ b/chrome/browser/printing/cloud_print/cloud_print_proxy_service.cc
@@ -89,7 +89,12 @@ void CloudPrintProxyService::Initialize() {
   }
 
   pref_change_registrar_.Init(profile_->GetPrefs());
-  pref_change_registrar_.Add(prefs::kCloudPrintProxyEnabled, this);
+  pref_change_registrar_.Add(
+      prefs::kCloudPrintProxyEnabled,
+      base::Bind(
+          base::IgnoreResult(
+              &CloudPrintProxyService::ApplyCloudPrintConnectorPolicy),
+          base::Unretained(this)));
 }
 
 void CloudPrintProxyService::RefreshStatusFromService() {
@@ -207,11 +212,6 @@ void CloudPrintProxyService::OnCloudPrintSetupClosed() {
       FROM_HERE, base::Bind(&browser::EndKeepAlive));
 }
 
-void CloudPrintProxyService::OnPreferenceChanged(PrefServiceBase* service,
-                                                 const std::string& pref_name) {
-  ApplyCloudPrintConnectorPolicy();
-}
-
 void CloudPrintProxyService::RefreshCloudPrintProxyStatus() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   ServiceProcessControl* process_control = GetServiceProcessControl();