[Sync] Replace typedef with using.

components/sync/base/ordinal_unittest.cc

 // 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.
 
 #include "components/sync/base/ordinal.h"
 
 #include <cctype>
 #include <vector>
 
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 13 matching lines @@
   static const uint8_t kMaxDigit = '9';
   static const size_t kMinLength = 5;
 };
 
 struct LargeOrdinalTraits {
   static const uint8_t kZeroDigit = 0;
   static const uint8_t kMaxDigit = UINT8_MAX;
   static const size_t kMinLength = 1;
 };
 
-typedef Ordinal<TestOrdinalTraits> TestOrdinal;
-typedef Ordinal<LongOrdinalTraits> LongOrdinal;
-typedef Ordinal<LargeOrdinalTraits> LargeOrdinal;
+using TestOrdinal = Ordinal<TestOrdinalTraits>;
+using LongOrdinal = Ordinal<LongOrdinalTraits>;
+using LargeOrdinal = Ordinal<LargeOrdinalTraits>;
 
 static_assert(TestOrdinal::kZeroDigit == '0',
               "incorrect TestOrdinal zero digit");
 static_assert(TestOrdinal::kOneDigit == '1', "incorrect TestOrdinal one digit");
 static_assert(TestOrdinal::kMidDigit == '2', "incorrect TestOrdinal min digit");
 static_assert(TestOrdinal::kMaxDigit == '3', "incorrect TestOrdinal max digit");
 static_assert(TestOrdinal::kMidDigitValue == 2,
               "incorrect TestOrdinal mid digit value");
 static_assert(TestOrdinal::kMaxDigitValue == 3,
               "incorrect TestOrdinal max digit value");
@@ skipping 305 matching lines @@
   std::vector<LongOrdinal> ordinals = sorted_ordinals;
   std::random_shuffle(ordinals.begin(), ordinals.end());
   std::sort(ordinals.begin(), ordinals.end(), LongOrdinal::LessThanFn());
   EXPECT_TRUE(std::equal(ordinals.begin(), ordinals.end(),
                          sorted_ordinals.begin(), LongOrdinal::EqualsFn()));
 }
 
 }  // namespace
 
 }  // namespace syncer