Reduce FOR_EACH_OBSERVER usage in ui/

ui/base/clipboard/clipboard_monitor.cc

 // Copyright (c) 2016 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 "ui/base/clipboard/clipboard_monitor.h"
 
 #include "ui/base/clipboard/clipboard.h"
 #include "ui/base/clipboard/clipboard_observer.h"
 
 namespace ui {
 
 ClipboardMonitor::ClipboardMonitor() {}
 
 ClipboardMonitor::~ClipboardMonitor() {
   DCHECK(CalledOnValidThread());
 }
 
 // static
 ClipboardMonitor* ClipboardMonitor::GetInstance() {
   return base::Singleton<ClipboardMonitor,
                          base::LeakySingletonTraits<ClipboardMonitor>>::get();
 }
 
 void ClipboardMonitor::NotifyClipboardDataChanged() {
   DCHECK(CalledOnValidThread());
-  FOR_EACH_OBSERVER(ClipboardObserver, observers_, OnClipboardDataChanged());
+  for (ClipboardObserver& observer : observers_)
+    observer.OnClipboardDataChanged();
 }
 
 void ClipboardMonitor::AddObserver(ClipboardObserver* observer) {
   DCHECK(CalledOnValidThread());
   observers_.AddObserver(observer);
 }
 
 void ClipboardMonitor::RemoveObserver(ClipboardObserver* observer) {
   DCHECK(CalledOnValidThread());
   observers_.RemoveObserver(observer);
 }
 
 }  // namespace ui