Reduce FOR_EACH_OBSERVER usage in ui/

ui/ozone/platform/drm/mus_thread_proxy.cc

 // Copyright 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/ozone/platform/drm/mus_thread_proxy.h"
 
 #include "base/bind.h"
 #include "base/single_thread_task_runner.h"
 #include "base/task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
@@ skipping 24 matching lines @@
 
 MusThreadProxy::MusThreadProxy()
     : ws_task_runner_(base::ThreadTaskRunnerHandle::Get()),
       drm_thread_(nullptr),
       weak_ptr_factory_(this) {}
 
 void MusThreadProxy::InitializeOnEvdev() {}
 
 MusThreadProxy::~MusThreadProxy() {
   DCHECK(on_window_server_thread_.CalledOnValidThread());
-  FOR_EACH_OBSERVER(GpuThreadObserver, gpu_thread_observers_,
-                    OnGpuThreadRetired());
+  for (GpuThreadObserver& observer : gpu_thread_observers_)
+    observer.OnGpuThreadRetired();
 }
 
 // This is configured on the GPU thread.
 void MusThreadProxy::SetDrmThread(DrmThread* thread) {
   base::AutoLock acquire(lock_);
   drm_thread_ = thread;
 }
 
 void MusThreadProxy::ProvideManagers(DrmDisplayHostManager* display_manager,
                                      DrmOverlayManager* overlay_manager) {
@@ skipping 10 matching lines @@
                             base::Unretained(this)));
 }
 
 void MusThreadProxy::DispatchObserversFromDrmThread() {
   ws_task_runner_->PostTask(FROM_HERE, base::Bind(&MusThreadProxy::RunObservers,
                                                   base::Unretained(this)));
 }
 
 void MusThreadProxy::RunObservers() {
   DCHECK(on_window_server_thread_.CalledOnValidThread());
-  FOR_EACH_OBSERVER(GpuThreadObserver, gpu_thread_observers_,
-                    OnGpuThreadReady());
+  for (GpuThreadObserver& observer : gpu_thread_observers_)
+    observer.OnGpuThreadReady();
 }
 
 void MusThreadProxy::AddGpuThreadObserver(GpuThreadObserver* observer) {
   DCHECK(on_window_server_thread_.CalledOnValidThread());
 
   gpu_thread_observers_.AddObserver(observer);
   if (IsConnected())
     observer->OnGpuThreadReady();
 }
 
@@ skipping 261 matching lines @@
   display_manager_->GpuReceivedHDCPState(display_id, success, state);
 }
 
 void MusThreadProxy::GpuSetHDCPStateCallback(int64_t display_id,
                                              bool success) const {
   DCHECK(on_window_server_thread_.CalledOnValidThread());
   display_manager_->GpuUpdatedHDCPState(display_id, success);
 }
 
 }  // namespace ui