Use a direct include of strings headers in content/test/, content/worker/.

content/test/image_decoder_test.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/test/image_decoder_test.h"
 
 #include "base/file_util.h"
 #include "base/files/file_enumerator.h"
 #include "base/files/file_path.h"
 #include "base/md5.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "third_party/WebKit/public/platform/WebData.h"
 #include "third_party/WebKit/public/platform/WebImage.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebImageDecoder.h"
 
 using base::Time;
 
 namespace {
 
 const int kFirstFrameIndex = 0;
@@ skipping 193 matching lines @@
   // Since WebImage does not expose get data by frame, get the size
   // through decoder and pass it to fromData so that the closest
   // image dats to the size is returned.
   WebKit::WebSize size(decoder->getImage(desired_frame_index).size());
   const WebKit::WebImage& image = WebKit::WebImage::fromData(data, size);
   SaveMD5Sum(md5_sum_path, image);
 #else
   VerifyImage(*decoder, image_path, md5_sum_path, desired_frame_index);
 #endif
 }