cros: Remove unused method

chrome/browser/chromeos/login/screens/hid_detection_screen.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 CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_HID_DETECTION_SCREEN_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_HID_DETECTION_SCREEN_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 30 matching lines @@
    public:
     virtual ~Delegate() {}
     virtual void OnHIDScreenNecessityCheck(bool screen_needed) = 0;
   };
 
   HIDDetectionScreen(BaseScreenDelegate* base_screen_delegate,
                      HIDDetectionView* view);
   ~HIDDetectionScreen() override;
 
   // HIDDetectionModel implementation:
-  void PrepareToShow() override;
   void Show() override;
   void Hide() override;
   void Initialize(::login::ScreenContext* context) override;
   void OnContinueButtonClicked() override;
   void OnViewDestroyed(HIDDetectionView* view) override;
   void CheckIsScreenRequired(
       const base::Callback<void(bool)>& on_check_done) override;
 
   // device::BluetoothDevice::PairingDelegate implementation:
   void RequestPinCode(device::BluetoothDevice* device) override;
@@ skipping 149 matching lines @@
   bool showing_;
 
   base::WeakPtrFactory<HIDDetectionScreen> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HIDDetectionScreen);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_HID_DETECTION_SCREEN_H_