Use a direct include of strings headers in ui/, part 3.

ui/web_dialogs/web_dialog_ui.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 UI_WEB_DIALOGS_WEB_DIALOG_UI_H_
 #define UI_WEB_DIALOGS_WEB_DIALOG_UI_H_
 
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_ui_controller.h"
 #include "googleurl/src/gurl.h"
 #include "ui/base/ui_base_types.h"
 #include "ui/web_dialogs/web_dialogs_export.h"
 
 namespace content {
 class WebContents;
 class WebUIMessageHandler;
 struct ContextMenuParams;
@@ skipping 64 matching lines @@
 // cloud print dialog).
 class WEB_DIALOGS_EXPORT ExternalWebDialogUI : public WebDialogUI {
  public:
   explicit ExternalWebDialogUI(content::WebUI* web_ui);
   virtual ~ExternalWebDialogUI();
 };
 
 }  // namespace ui
 
 #endif  // UI_WEB_DIALOGS_WEB_DIALOG_UI_H_