certificate manager: Disable export option for TPM-backed certs.

net/base/cert_database.h

 // Copyright (c) 2012 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 NET_BASE_CERT_DATABASE_H_
 #define NET_BASE_CERT_DATABASE_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 154 matching lines @@
                         ImportCertFailureList* not_imported);
 
   // Get trust bits for certificate.
   TrustBits GetCertTrust(const X509Certificate* cert, CertType type) const;
 
   // IsUntrusted returns true if |cert| is specifically untrusted. These
   // certificates are stored in the database for the specific purpose of
   // rejecting them.
   bool IsUntrusted(const X509Certificate* cert) const;
 
+  // IsHardwareBacked returns true if |cert| is hardware backed.
+  bool IsHardwareBacked(const X509Certificate* cert) const;
+
   // Set trust values for certificate.
   // Returns true on success or false on failure.
   bool SetCertTrust(const X509Certificate* cert,
                     CertType type,
                     TrustBits trust_bits);
 
   // Delete certificate and associated private key (if one exists).
   // |cert| is still valid when this function returns. Returns true on
   // success.
   bool DeleteCertAndKey(const X509Certificate* cert);
@@ skipping 16 matching lines @@
   static void NotifyObserversOfUserCertAdded(const X509Certificate* cert);
   static void NotifyObserversOfUserCertRemoved(const X509Certificate* cert);
   static void NotifyObserversOfCertTrustChanged(const X509Certificate* cert);
 
   DISALLOW_COPY_AND_ASSIGN(CertDatabase);
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_CERT_DATABASE_H_