Use the exact-width integer types defined in <stdint.h> rather than

net/cert/signed_tree_head.h

 // 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.
 
 #ifndef NET_CERT_SIGNED_TREE_HEAD_H_
 #define NET_CERT_SIGNED_TREE_HEAD_H_
 
 #include <string>
 #include <vector>
 
 #include "base/time/time.h"
 #include "net/base/hash_value.h"
 #include "net/base/net_export.h"
 #include "net/cert/signed_certificate_timestamp.h"
 
 namespace net {
 
 namespace ct {
 
-static const uint8 kSthRootHashLength = 32;
+static const uint8_t kSthRootHashLength = 32;
 
 // Signed Tree Head as defined in section 3.5. of RFC6962
 struct NET_EXPORT SignedTreeHead {
   // Version enum in RFC 6962, Section 3.2. Note that while in the current
   // RFC the STH and SCT share the versioning scheme, there are plans in
   // RFC6962-bis to use separate versions, so using a separate scheme here.
   enum Version { V1 = 0, };
 
   Version version;
   base::Time timestamp;
-  uint64 tree_size;
+  uint64_t tree_size;
   char sha256_root_hash[kSthRootHashLength];
   DigitallySigned signature;
 };
 
 }  // namespace ct
 
 }  // namespace net
 
 #endif