Use size_t in crypto::SignatureVerifier.

components/client_update_protocol/ecdsa.cc

 // Copyright 2016 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 "components/client_update_protocol/ecdsa.h"
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 152 matching lines @@
   signed_message.insert(signed_message.end(), response_hash.begin(),
                         response_hash.end());
   signed_message.insert(signed_message.end(), request_query_cup2key_.begin(),
                         request_query_cup2key_.end());
 
   const std::vector<uint8_t> signed_message_hash =
       SHA256HashVec(signed_message);
 
   // Initialize the signature verifier.
   crypto::SignatureVerifier verifier;
-  if (!verifier.VerifyInit(
-          crypto::SignatureVerifier::ECDSA_SHA256, &signature.front(),
-          static_cast<int>(signature.size()), &public_key_.front(),
-          static_cast<int>(public_key_.size()))) {
+  if (!verifier.VerifyInit(crypto::SignatureVerifier::ECDSA_SHA256,
+                           &signature.front(), signature.size(),
+                           &public_key_.front(), public_key_.size())) {
     DVLOG(1) << "Couldn't init SignatureVerifier.";
     return false;
   }
 
   // If the verification fails, that implies one of two outcomes:
   // * The signature was modified
   // * The buffer that the server signed does not match the buffer that the
   //   client assembled -- implying that either request body or response body
   //   was modified, or a different nonce value was used.
   verifier.VerifyUpdate(&signed_message_hash.front(),
-                        static_cast<int>(signed_message_hash.size()));
+                        signed_message_hash.size());
   return verifier.VerifyFinal();
 }
 
 }  // namespace client_update_protocol