Fix ChromeOS clang build after original change was reverted.

chrome/browser/automation/testing_automation_provider_chromeos.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/automation/testing_automation_provider.h"
 
 #include "base/command_line.h"
 #include "base/i18n/time_formatting.h"
 #include "base/stringprintf.h"
 #include "base/time.h"
@@ skipping 1110 matching lines @@
   views::Widget* window = browser::CreateViewsWindow(
       browser->window()->GetNativeHandle(), take_photo_dialog, STYLE_GENERIC);
   window->SetAlwaysOnTop(true);
   window->Show();
 }
 
 void TestingAutomationProvider::PowerChanged(
     const chromeos::PowerSupplyStatus& status) {
   power_status = status;
 }
-
-void TestingAutomationProvider::LockScreen() {
-  // Not used, but defined to make clang happy with the overloaded name.
-}
-
-void TestingAutomationProvider::UnlockScreen() {
-  // Not used, but defined to make clang happy with the overloaded name.
-}