Use a direct include of strings headers in crypto/, dbus/, device/.

crypto/symmetric_key_unittest.cc

 // Copyright (c) 2011 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 "crypto/symmetric_key.h"
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
-#include "base/string_number_conversions.h"
-#include "base/string_util.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 TEST(SymmetricKeyTest, GenerateRandomKey) {
   scoped_ptr<crypto::SymmetricKey> key(
       crypto::SymmetricKey::GenerateRandomKey(crypto::SymmetricKey::AES, 256));
   ASSERT_TRUE(NULL != key.get());
   std::string raw_key;
   EXPECT_TRUE(key->GetRawKey(&raw_key));
   EXPECT_EQ(32U, raw_key.size());
 
@@ skipping 194 matching lines @@
     "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
     "pass phrase exceeds block size",
     20,
     256,
     "e0739745dc28b8721ba402e05214d2ac1eab54cf72bee1fba388297a09eb493c",
   },
 };
 
 INSTANTIATE_TEST_CASE_P(, SymmetricKeyDeriveKeyFromPasswordTest,
                         testing::ValuesIn(kTestVectors));