Clean up HID backend and API.

device/hid/hid_service_mac.h

-// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// 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_HID_SERVICE_MAC_H_
 #define DEVICE_HID_HID_SERVICE_MAC_H_
 
-#include <map>
+#include <CoreFoundation/CoreFoundation.h>
+#include <IOKit/hid/IOHIDManager.h>
 #include <string>
-#include <vector>
 
-#include "base/basictypes.h"
 #include "base/mac/foundation_util.h"
 #include "base/memory/ref_counted.h"
-#include "base/memory/singleton.h"
-#include "base/message_loop/message_loop.h"
-#include "base/strings/string16.h"
-#include "base/synchronization/waitable_event.h"
-#include "base/threading/thread.h"
-#include "base/threading/thread_checker.h"
-#include "build/build_config.h"
-#include "device/hid/hid_device_info.h"
 #include "device/hid/hid_service.h"
 
-#include <CoreFoundation/CoreFoundation.h>
-#include <IOKit/hid/IOHIDManager.h>
+namespace base {
+class MessageLoopProxy;
+}
 
 namespace device {
 
 class HidConnection;
-class HidService;
 
 class HidServiceMac : public HidService {
  public:
   HidServiceMac();
 
-  virtual scoped_refptr<HidConnection> Connect(std::string device_id) OVERRIDE;
+  virtual scoped_refptr<HidConnection> Connect(const std::string& device_id)
+      OVERRIDE;
 
  private:
   virtual ~HidServiceMac();
 
-  void ScheduleRunLoop();
-  void UnscheduleRunLoop();
+  void StartWatchingDevices();
+  void StopWatchingDevices();
 
   // Device changing callbacks.
   static void AddDeviceCallback(void* context,
                                 IOReturn result,
                                 void* sender,
-                                IOHIDDeviceRef ref);
+                                IOHIDDeviceRef hid_device);
   static void RemoveDeviceCallback(void* context,
                                    IOReturn result,
                                    void* sender,
-                                   IOHIDDeviceRef ref);
-  static HidServiceMac* InstanceFromContext(void* context);
+                                   IOHIDDeviceRef hid_device);
 
-  IOHIDDeviceRef FindDevice(std::string id);
+  IOHIDDeviceRef FindDevice(const std::string& device_id);
 
   void Enumerate();
 
-  void PlatformAddDevice(IOHIDDeviceRef ref);
-  void PlatformRemoveDevice(IOHIDDeviceRef ref);
-
-  // The message loop this object belongs to.
-  scoped_refptr<base::MessageLoopProxy> message_loop_;
+  void PlatformAddDevice(IOHIDDeviceRef hid_device);
+  void PlatformRemoveDevice(IOHIDDeviceRef hid_device);
 
   // Platform HID Manager
-  base::ScopedCFTypeRef<IOHIDManagerRef> hid_manager_ref_;
+  base::ScopedCFTypeRef<IOHIDManagerRef> hid_manager_;
 
-  // Enumeration thread.
-  scoped_ptr<base::Thread> enumeration_runloop_thread_;
-  CFRunLoopRef enumeration_runloop_;
-  base::WaitableEvent enumeration_runloop_init_;
-
-  bool available_;
+  // The message loop for the thread on which this service was created.
+  scoped_refptr<base::MessageLoopProxy> message_loop_;
 
   DISALLOW_COPY_AND_ASSIGN(HidServiceMac);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_HID_HID_SERVICE_MAC_H_