Convert zoom callbacks to use CallbackRegistry

chrome/browser/profiles/profile_impl.cc

Index: chrome/browser/profiles/profile_impl.cc
diff --git a/chrome/browser/profiles/profile_impl.cc b/chrome/browser/profiles/profile_impl.cc
index 9a62d382d7258874903c579fd165c4f30d7e1d9b..b4e994adb3a31c04952dcad77b6867d2867f16fc 100644
--- a/chrome/browser/profiles/profile_impl.cc
+++ b/chrome/browser/profiles/profile_impl.cc
@@ -373,9 +373,7 @@ ProfileImpl::ProfileImpl(
     Delegate* delegate,
     CreateMode create_mode,
     base::SequencedTaskRunner* sequenced_task_runner)
-    : zoom_callback_(base::Bind(&ProfileImpl::OnZoomLevelChanged,
-                                base::Unretained(this))),
-      path_(path),
+    : path_(path),
       pref_registry_(new user_prefs::PrefRegistrySyncable),
       io_data_(this),
       host_content_settings_map_(NULL),
@@ -631,7 +629,8 @@ void ProfileImpl::InitHostZoomMap() {
     }
   }
 
-  host_zoom_map->AddZoomLevelChangedCallback(zoom_callback_);
+  zoom_subscription_ = host_zoom_map->AddZoomLevelChangedCallback(
+      base::Bind(&ProfileImpl::OnZoomLevelChanged, base::Unretained(this)));
 }
 
 base::FilePath ProfileImpl::last_selected_directory() {
@@ -645,9 +644,6 @@ void ProfileImpl::set_last_selected_directory(const base::FilePath& path) {
 ProfileImpl::~ProfileImpl() {
   MaybeSendDestroyedNotification();
 
-  HostZoomMap::GetForBrowserContext(this)->RemoveZoomLevelChangedCallback(
-      zoom_callback_);
-
   bool prefs_loaded = prefs_->GetInitializationStatus() !=
       PrefService::INITIALIZATION_STATUS_WAITING;