Replace more ObserverList with base::ObserverList.

device/hid/input_service_linux.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_HID_INPUT_SERVICE_LINUX_H_
 #define DEVICE_HID_INPUT_SERVICE_LINUX_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 66 matching lines @@
   void WillDestroyCurrentMessageLoop() override;
 
  protected:
 
   void AddDevice(const InputDeviceInfo& info);
   void RemoveDevice(const std::string& id);
 
   bool CalledOnValidThread() const;
 
   DeviceMap devices_;
-  ObserverList<Observer> observers_;
+  base::ObserverList<Observer> observers_;
 
  private:
   friend struct base::DefaultDeleter<InputServiceLinux>;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(InputServiceLinux);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_HID_INPUT_SERVICE_LINUX_H_