Use a direct include of strings headers in content/renderer and content/shell.

content/renderer/renderer_main_platform_delegate_win.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 "content/renderer/renderer_main_platform_delegate.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "base/win/win_util.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/injection_test_win.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/renderer/render_thread_impl.h"
 #include "sandbox/win/src/sandbox.h"
 #include "skia/ext/vector_platform_device_emf_win.h"
 #include "third_party/icu/public/i18n/unicode/timezone.h"
 #include "third_party/skia/include/ports/SkTypeface_win.h"
 
@@ skipping 142 matching lines @@
     if (run_security_tests) {
       int test_count = 0;
       DVLOG(1) << "Running renderer security tests";
       BOOL result = run_security_tests(&test_count);
       CHECK(result) << "Test number " << test_count << " has failed.";
     }
   }
 }
 
 }  // namespace content