Move off of deprecated base::NonThreadSafe in device/

device/usb/usb_service.h

 // 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.
 
 #ifndef DEVICE_USB_USB_SERVICE_H_
 #define DEVICE_USB_USB_SERVICE_H_
 
 #include <memory>
 #include <string>
 #include <unordered_map>
 #include <unordered_set>
 #include <vector>
 
 #include "base/bind_helpers.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/observer_list.h"
+#include "base/sequence_checker.h"
 #include "base/sequenced_task_runner.h"
 #include "base/single_thread_task_runner.h"
 #include "base/task_scheduler/task_traits.h"
-#include "base/threading/non_thread_safe.h"
 
 namespace device {
 
 class UsbDevice;
 
 // The USB service handles creating and managing an event handler thread that is
 // used to manage and dispatch USB events. It is also responsible for device
 // discovery on the system, which allows it to re-use device handles to prevent
 // competition for the same USB device.
-class UsbService : public base::NonThreadSafe {
+class UsbService {
  public:
   using GetDevicesCallback =
       base::Callback<void(const std::vector<scoped_refptr<UsbDevice>>&)>;
 
   class Observer {
    public:
     virtual ~Observer();
 
     // These events are delivered from the thread on which the UsbService object
     // was created.
@@ skipping 46 matching lines @@
   }
 
   const scoped_refptr<base::SequencedTaskRunner>& blocking_task_runner() const {
     return blocking_task_runner_;
   }
 
   std::unordered_map<std::string, scoped_refptr<UsbDevice>>& devices() {
     return devices_;
   }
 
+  SEQUENCE_CHECKER(sequence_checker_);
+
  private:
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
   std::unordered_map<std::string, scoped_refptr<UsbDevice>> devices_;
   std::unordered_set<std::string> testing_devices_;
   base::ObserverList<Observer, true> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(UsbService);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_USB_USB_SERVICE_H_