Use a direct include of strings headers in content/p*/.

content/public/common/context_menu_params.h

 // 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.
 
 #ifndef CONTENT_PUBLIC_COMMON_CONTEXT_MENU_PARAMS_H_
 #define CONTENT_PUBLIC_COMMON_CONTEXT_MENU_PARAMS_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
-#include "base/string16.h"
-#include "googleurl/src/gurl.h"
+#include "base/strings/string16.h"
 #include "content/common/content_export.h"
 #include "content/public/common/page_state.h"
 #include "content/public/common/ssl_status.h"
+#include "googleurl/src/gurl.h"
 #include "third_party/WebKit/public/platform/WebReferrerPolicy.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebContextMenuData.h"
 #include "webkit/glue/webmenuitem.h"
 
 #if defined(OS_ANDROID)
 #include "ui/gfx/point.h"
 #endif
 
 namespace content {
 
@@ skipping 124 matching lines @@
   // end of the selection, if there is one.
   gfx::Point selection_start;
   gfx::Point selection_end;
 #endif
 
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_COMMON_CONTEXT_MENU_PARAMS_H_