move favicon download code from chrome/ into content/

chrome/common/favicon_url.h

-// Copyright (c) 2011 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_COMMON_FAVICON_URL_
-#define CHROME_COMMON_FAVICON_URL_
-
-#include "googleurl/src/gurl.h"
-
-// The favicon url from the render.
-struct FaviconURL {
-  // The icon type in a page. The definition must be same as history::IconType.
-  enum IconType {
-    INVALID_ICON = 0x0,
-    FAVICON = 1 << 0,
-    TOUCH_ICON = 1 << 1,
-    TOUCH_PRECOMPOSED_ICON = 1 << 2
-  };
-
-  FaviconURL();
-  FaviconURL(const GURL& url, IconType type);
-  ~FaviconURL();
-
-  // The url of the icon.
-  GURL icon_url;
-
-  // The type of the icon
-  IconType icon_type;
-};
-
-#endif  // CHROME_COMMON_FAVICON_URL_