Update from https://crrev.com/306655

net/quic/crypto/quic_crypto_server_config.cc

 // Copyright 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 "net/quic/crypto/quic_crypto_server_config.h"
 
 #include <stdlib.h>
 #include <algorithm>
 
 #include "base/stl_util.h"
@@ skipping 233 matching lines @@
   CryptoHandshakeMessage msg;
 
   const string curve25519_private_key =
       Curve25519KeyExchange::NewPrivateKey(rand);
   scoped_ptr<Curve25519KeyExchange> curve25519(
       Curve25519KeyExchange::New(curve25519_private_key));
   StringPiece curve25519_public_value = curve25519->public_value();
 
   string encoded_public_values;
   // First three bytes encode the length of the public value.
-  encoded_public_values.push_back(curve25519_public_value.size());
-  encoded_public_values.push_back(curve25519_public_value.size() >> 8);
-  encoded_public_values.push_back(curve25519_public_value.size() >> 16);
+  DCHECK_LT(curve25519_public_value.size(), (1U << 24));
+  encoded_public_values.push_back(
+      static_cast<char>(curve25519_public_value.size()));
+  encoded_public_values.push_back(
+      static_cast<char>(curve25519_public_value.size() >> 8));
+  encoded_public_values.push_back(
+      static_cast<char>(curve25519_public_value.size() >> 16));
   encoded_public_values.append(curve25519_public_value.data(),
                                curve25519_public_value.size());
 
   string p256_private_key;
   if (options.p256) {
     p256_private_key = P256KeyExchange::NewPrivateKey();
     scoped_ptr<P256KeyExchange> p256(P256KeyExchange::New(p256_private_key));
     StringPiece p256_public_value = p256->public_value();
 
-    encoded_public_values.push_back(p256_public_value.size());
-    encoded_public_values.push_back(p256_public_value.size() >> 8);
-    encoded_public_values.push_back(p256_public_value.size() >> 16);
+    DCHECK_LT(p256_public_value.size(), (1U << 24));
+    encoded_public_values.push_back(
+        static_cast<char>(p256_public_value.size()));
+    encoded_public_values.push_back(
+        static_cast<char>(p256_public_value.size() >> 8));
+    encoded_public_values.push_back(
+        static_cast<char>(p256_public_value.size() >> 16));
     encoded_public_values.append(p256_public_value.data(),
                                  p256_public_value.size());
   }
 
   msg.set_tag(kSCFG);
   if (options.p256) {
     msg.SetTaglist(kKEXS, kC255, kP256, 0);
   } else {
     msg.SetTaglist(kKEXS, kC255, 0);
   }
@@ skipping 1279 matching lines @@
 QuicCryptoServerConfig::Config::Config()
     : channel_id_enabled(false),
       is_primary(false),
       primary_time(QuicWallTime::Zero()),
       priority(0),
       source_address_token_boxer(nullptr) {}
 
 QuicCryptoServerConfig::Config::~Config() { STLDeleteElements(&key_exchanges); }
 
 }  // namespace net