[Cleanup] Move the Easy Unlock metrics files out of the chromeos directory.

chrome/browser/chromeos/login/easy_unlock/easy_unlock_metrics.cc

-// 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.
-
-#include "chrome/browser/chromeos/login/easy_unlock/easy_unlock_metrics.h"
-
-#include "base/logging.h"
-#include "base/metrics/histogram.h"
-
-namespace chromeos {
-
-void RecordEasyUnlockLoginEvent(EasyUnlockLoginEvent event) {
-  DCHECK_LT(event, EASY_SIGN_IN_LOGIN_EVENT_COUNT);
-
-  UMA_HISTOGRAM_ENUMERATION("EasyUnlock.SignIn.LoginEvent",
-                            event,
-                            EASY_SIGN_IN_LOGIN_EVENT_COUNT);
-}
-
-}  // namespace chromeos