Extract a minimal subset of WebDialogUI/WebDialogDelegate from src/chrome -> src/ui/web_dialogs

chrome/browser/ui/webui/external_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 CHROME_BROWSER_UI_WEBUI_EXTERNAL_WEB_DIALOG_UI_H_
+#define CHROME_BROWSER_UI_WEBUI_EXTERNAL_WEB_DIALOG_UI_H_
+#pragma once
+
+#include <string>
+#include <vector>
+
+#include "base/compiler_specific.h"
+#include "base/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_dialog_ui.h"
+
+
+namespace base {
+class ListValue;
+template<class T> class PropertyAccessor;
+}
+
+namespace content {
+class WebContents;
+class WebUIMessageHandler;
+struct ContextMenuParams;
+}
+
+namespace gfx {
+class Size;
+}
+
+// Displays external URL contents inside a modal web dialog.
+//
+// Intended to be the place to collect the settings and lockdowns
+// necessary for running external UI components securely (e.g., the
+// cloud print dialog).
+class ExternalWebDialogUI : public web_dialogs::WebDialogUI {
+ public:
+  explicit ExternalWebDialogUI(content::WebUI* web_ui);
+  virtual ~ExternalWebDialogUI();
+};
+
+#endif  // CHROME_BROWSER_UI_WEBUI_EXTERNAL_WEB_DIALOG_UI_H_