Reduce usage of FOR_EACH_OBSERVER macro in components/

components/zoom/zoom_event_manager.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/zoom/zoom_event_manager.h"
 
 #include "components/zoom/zoom_event_manager_observer.h"
 #include "content/public/browser/browser_context.h"
 
 namespace {
@@ skipping 19 matching lines @@
   zoom_level_changed_callbacks_.Notify(change);
 }
 
 std::unique_ptr<content::HostZoomMap::Subscription>
 ZoomEventManager::AddZoomLevelChangedCallback(
     const content::HostZoomMap::ZoomLevelChangedCallback& callback) {
   return zoom_level_changed_callbacks_.Add(callback);
 }
 
 void ZoomEventManager::OnDefaultZoomLevelChanged() {
-  FOR_EACH_OBSERVER(ZoomEventManagerObserver, observers_,
-                    OnDefaultZoomLevelChanged());
+  for (auto& observer : observers_)
+    observer.OnDefaultZoomLevelChanged();
 }
 
 void ZoomEventManager::AddZoomEventManagerObserver(
     ZoomEventManagerObserver* observer) {
   observers_.AddObserver(observer);
 }
 
 void ZoomEventManager::RemoveZoomEventManagerObserver(
     ZoomEventManagerObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
 }  // namespace zoom