linux and chromeos: Turn on -Wunused-const-variable.

chrome/browser/chromeos/attestation/attestation_policy_observer.cc

 // Copyright (c) 2013 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/attestation/attestation_policy_observer.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/location.h"
 #include "base/time/time.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/attestation/attestation_ca_client.h"
 #include "chrome/browser/chromeos/attestation/attestation_key_payload.pb.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/policy/cloud/cloud_policy_client.h"
 #include "chrome/browser/policy/cloud/cloud_policy_manager.h"
 #include "chromeos/attestation/attestation_flow.h"
 #include "chromeos/cryptohome/async_method_caller.h"
 #include "chromeos/dbus/cryptohome_client.h"
 #include "chromeos/dbus/dbus_method_call_status.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_details.h"
 #include "net/cert/x509_certificate.h"
 
 namespace {
 
-const char kEnterpriseMachineKey[] = "attest-ent-machine";
-
 // The number of days before a certificate expires during which it is
 // considered 'expiring soon' and replacement is initiated.  The Chrome OS CA
 // issues certificates with an expiry of at least two years.  This value has
 // been set large enough so that the majority of users will have gone through
 // a full sign-in during the period.
 const int kExpiryThresholdInDays = 30;
 const int kRetryDelay = 5;  // Seconds.
 const int kRetryLimit = 100;
 
 // A dbus callback which handles a boolean result.
@@ skipping 259 matching lines @@
         base::Bind(&AttestationPolicyObserver::Start,
                    weak_factory_.GetWeakPtr()),
         base::TimeDelta::FromSeconds(retry_delay_));
   } else {
     LOG(WARNING) << "AttestationPolicyObserver: Retry limit exceeded.";
   }
 }
 
 }  // namespace attestation
 }  // namespace chromeos