Move device monitors out of //media/capture into //media/device_monitors

media/capture/device_monitor_mac.h

Index: media/capture/device_monitor_mac.h
diff --git a/media/capture/device_monitor_mac.h b/media/capture/device_monitor_mac.h
deleted file mode 100644
index c6db8b9da926616b8900f9beb711ee7a7835ef2d..0000000000000000000000000000000000000000
--- a/media/capture/device_monitor_mac.h
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright (c) 2012 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.
-
-#ifndef MEDIA_CAPTURE_DEVICE_MONITOR_MAC_H_
-#define MEDIA_CAPTURE_DEVICE_MONITOR_MAC_H_
-
-#include <memory>
-
-#include "base/macros.h"
-#include "base/system_monitor/system_monitor.h"
-#include "base/threading/thread_checker.h"
-#include "media/capture/capture_export.h"
-
-namespace {
-class DeviceMonitorMacImpl;
-}
-
-namespace media {
-
-// Class to track audio/video devices removal or addition via callback to
-// base::SystemMonitor ProcessDevicesChanged(). A single object of this class
-// is created from the browser main process and lives as long as this one.
-class CAPTURE_EXPORT DeviceMonitorMac {
- public:
-  DeviceMonitorMac();
-  ~DeviceMonitorMac();
-
-  // Registers the observers for the audio/video device removal, connection and
-  // suspension. The AVFoundation library is also loaded and initialised if the
-  // OS supports it. The |device_task_runner| argument represents the thread on
-  // which device enumeration will occur.
-  void StartMonitoring(
-      const scoped_refptr<base::SingleThreadTaskRunner>& device_task_runner);
-
-  // Method called by the internal DeviceMonitorMacImpl object
-  // |device_monitor_impl_| when a device of type |type| has been added to or
-  // removed from the system. This code executes in the notification thread.
-  void NotifyDeviceChanged(base::SystemMonitor::DeviceType type);
-
- private:
-  std::unique_ptr<DeviceMonitorMacImpl> device_monitor_impl_;
-
-  // |thread_checker_| is used to check that constructor and StartMonitoring()
-  // are called in the correct thread, the UI thread, that also owns the object.
-  base::ThreadChecker thread_checker_;
-
-  DISALLOW_COPY_AND_ASSIGN(DeviceMonitorMac);
-};
-
-}  // namespace content
-
-#endif  // MEDIA_CAPTURE_DEVICE_MONITOR_MAC_H_