Remove FOR_EACH_OBSERVER from arc/ since it's being deprecated

components/arc/arc_bridge_bootstrap.cc

 // Copyright 2015 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/arc/arc_bridge_bootstrap.h"
 
 #include <fcntl.h>
 #include <grp.h>
 #include <poll.h>
 #include <unistd.h>
@@ skipping 465 matching lines @@
     return;
   }
 
   mojom::ArcBridgeInstancePtr instance;
   instance.Bind(mojo::InterfacePtrInfo<mojom::ArcBridgeInstance>(
       std::move(server_pipe), 0u));
   arc_bridge_host_.reset(new ArcBridgeHostImpl(std::move(instance)));
 
   VLOG(2) << "Mojo is connected. ARC is running.";
   state_ = State::RUNNING;
-  FOR_EACH_OBSERVER(ArcBridgeBootstrap::Observer, observer_list_, OnReady());
+  for (auto& observer : observer_list_)
+    observer.OnReady();
 }
 
 void ArcBridgeBootstrapImpl::Stop() {
   DCHECK(thread_checker_.CalledOnValidThread());
   VLOG(2) << "Stopping ARC session is requested.";
 
   // For second time or later, just do nothing.
   // It is already in the stopping phase.
   if (stop_requested_)
     return;
@@ skipping 77 matching lines @@
   OnStopped(reason);
 }
 
 void ArcBridgeBootstrapImpl::OnStopped(ArcBridgeService::StopReason reason) {
   DCHECK(thread_checker_.CalledOnValidThread());
   // OnStopped() should be called once per instance.
   DCHECK_NE(state_, State::STOPPED);
   VLOG(2) << "ARC session is stopped.";
   arc_bridge_host_.reset();
   state_ = State::STOPPED;
-  FOR_EACH_OBSERVER(ArcBridgeBootstrap::Observer, observer_list_,
-                    OnStopped(reason));
+  for (auto& observer : observer_list_)
+    observer.OnStopped(reason);
 }
 
 }  // namespace
 
 ArcBridgeBootstrap::ArcBridgeBootstrap() = default;
 ArcBridgeBootstrap::~ArcBridgeBootstrap() = default;
 
 void ArcBridgeBootstrap::AddObserver(Observer* observer) {
   observer_list_.AddObserver(observer);
 }
 
 void ArcBridgeBootstrap::RemoveObserver(Observer* observer) {
   observer_list_.RemoveObserver(observer);
 }
 
 // static
 std::unique_ptr<ArcBridgeBootstrap> ArcBridgeBootstrap::Create() {
   return base::MakeUnique<ArcBridgeBootstrapImpl>();
 }
 
 }  // namespace arc