[Icons NTP] Refactor large_icon_source to extract the logic shared between desktop and Android to f…

components/favicon_base/favicon_callback.h

 // Copyright 2014 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 COMPONENTS_FAVICON_BASE_FAVICON_CALLBACK_H_
 #define COMPONENTS_FAVICON_BASE_FAVICON_CALLBACK_H_
 
 #include <vector>
 
 #include "base/callback.h"
 
 namespace favicon_base {
 
 struct FaviconRawBitmapResult;
 struct FaviconImageResult;
+struct LargeIconResult;
 
 // Callback for functions that can be used to return a |gfx::Image| and the
 // |GURL| it is loaded from. They are returned as a |FaviconImageResult| object.
 typedef base::Callback<void(const FaviconImageResult&)> FaviconImageCallback;
 
 // Callback for functions returning raw data for a favicon. In
 // |FaviconRawBitmapResult|, the data is not yet converted as a |gfx::Image|.
 typedef base::Callback<void(const FaviconRawBitmapResult&)>
     FaviconRawBitmapCallback;
 
 // Callback for functions returning raw data for a favicon in multiple
 // resolution. In |FaviconRawBitmapResult|, the data is not yet converted as a
 // |gfx::Image|.
 typedef base::Callback<void(const std::vector<FaviconRawBitmapResult>&)>
     FaviconResultsCallback;
 
+// Callback for functions returning data for a large icon. |LargeIconResult|
+// will contain either the raw bitmap for a large icon or the style of the
+// fallback to use if a sufficiently large icon could not be found.
+typedef base::Callback<void(const LargeIconResult&)> LargeIconCallback;
+
 }  // namespace favicon_base
 
 #endif  // COMPONENTS_FAVICON_BASE_FAVICON_CALLBACK_H_