attestation: Fix policy observer expiry check.

chrome/browser/chromeos/attestation/attestation_policy_observer.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_ATTESTATION_ATTESTATION_POLICY_OBSERVER_H_
 #define CHROME_BROWSER_CHROMEOS_ATTESTATION_ATTESTATION_POLICY_OBSERVER_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 45 matching lines @@
 
   // Checks attestation policy and starts any necessary work.
   void Start();
 
   // Gets a new certificate for the Enterprise Machine Key (EMK).
   void GetNewCertificate();
 
   // Gets the existing EMK certificate and sends it to CheckCertificateExpiry.
   void GetExistingCertificate();
 
-  // Checks if the given certificate is expired and, if so, get a new one.
+  // Checks if the given certificate is expired and, if so, gets a new one. The
+  // certificate data is assumed to actually be a chain of certificates in PEM
+  // format. All certificates in the chain are checked for expiry.
   void CheckCertificateExpiry(const std::string& certificate);

[Mattias Nissler (ping if slow), 2015/12/10 08:08:40]

nit: Please update the variable name to reflect the semantics, i.e.
|pem_certificate_chain| or somesuch.

 
   // Uploads a certificate to the policy server.
   void UploadCertificate(const std::string& certificate);
 
   // Checks if a certificate has already been uploaded and, if not, upload.
   void CheckIfUploaded(const std::string& certificate,
                        const std::string& key_payload);
 
   // Gets the payload associated with the EMK and sends it to |callback|.
   void GetKeyPayload(base::Callback<void(const std::string&)> callback);
@@ skipping 24 matching lines @@
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<AttestationPolicyObserver> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AttestationPolicyObserver);
 };
 
 }  // namespace attestation
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_ATTESTATION_ATTESTATION_POLICY_OBSERVER_H_