Use a direct include of strings headers in chrome/browser/r*-s*/.

chrome/browser/safe_browsing/ping_manager_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 "base/logging.h"
-#include "base/stringprintf.h"
+#include "base/strings/stringprintf.h"
 #include "base/time.h"
-#include "testing/gtest/include/gtest/gtest.h"
 #include "chrome/browser/safe_browsing/ping_manager.h"
 #include "google_apis/google_api_keys.h"
 #include "net/base/escape.h"
+#include "testing/gtest/include/gtest/gtest.h"
 
 using base::Time;
 using base::TimeDelta;
 
 static const char kUrlPrefix[] = "https://prefix.com/foo";
 static const char kClient[] = "unittest";
 static const char kAppVer[] = "1.0";
 
 class SafeBrowsingPingManagerTest : public testing::Test {
  protected:
@@ skipping 70 matching lines @@
   SafeBrowsingProtocolConfig config;
   config.client_name = kClient;
   config.url_prefix = kUrlPrefix;
   SafeBrowsingPingManager pm(NULL, config);
 
   pm.version_ = kAppVer;
   EXPECT_EQ("https://prefix.com/foo/clientreport/malware?"
             "client=unittest&appver=1.0&pver=1.0" + key_param_,
             pm.MalwareDetailsUrl().spec());
 }