Use a direct include of strings headers in content/browser/, part 1.

content/browser/gamepad/gamepad_platform_data_fetcher_mac.mm

 // 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/browser/gamepad/gamepad_platform_data_fetcher_mac.h"
 
 #include "base/mac/foundation_util.h"
 #include "base/memory/scoped_nsobject.h"
-#include "base/string16.h"
-#include "base/string_util.h"
+#include "base/strings/string16.h"
+#include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time.h"
 
 #include <IOKit/hid/IOHIDKeys.h>
 #import <Foundation/Foundation.h>
 
 using WebKit::WebGamepad;
 using WebKit::WebGamepads;
 
 namespace content {
@@ skipping 411 matching lines @@
   pads->length = WebGamepads::itemsLengthCap;
   for (size_t i = 0; i < WebGamepads::itemsLengthCap; ++i) {
     if (!associated_[i].is_xbox && associated_[i].hid.mapper)
       associated_[i].hid.mapper(data_.items[i], &pads->items[i]);
     else
       pads->items[i] = data_.items[i];
   }
 }
 
 }  // namespace content