[Large Icon Service] Move icon resizing into worker thread.

components/favicon/core/large_icon_service.h

-// Copyright (c) 2015 The Chromium Authors. All rights reserved.
+// Copyright 2015 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_CORE_LARGE_ICON_SERVICE_H_
 #define COMPONENTS_FAVICON_CORE_LARGE_ICON_SERVICE_H_
 
 #include <vector>
 
 #include "base/task/cancelable_task_tracker.h"
 #include "components/favicon_base/favicon_callback.h"
 #include "components/keyed_service/core/keyed_service.h"
 
 class GURL;
 
-namespace favicon_base {
-struct FaviconRawBitmapResult;
+namespace base {
+class TaskRunner;
 }
 
 namespace favicon {
 
 class FaviconService;
 
 // The large icon service provides methods to access large icons. It relies on
 // the favicon service.
 class LargeIconService : public KeyedService {
  public:
@@ skipping 12 matching lines @@
   // - Returns the default fallback icon style.
   // For cases 2 and 3, this function returns the style of the fallback icon
   // instead of rendering an icon so clients can render the icon themselves.
   base::CancelableTaskTracker::TaskId GetLargeIconOrFallbackStyle(
     const GURL& page_url,
     int min_source_size_in_pixel,
     int desired_size_in_pixel,
     const favicon_base::LargeIconCallback& callback,
     base::CancelableTaskTracker* tracker);
 
+  // Returns TaskRunner used to execute background task.
+  virtual scoped_refptr<base::TaskRunner> GetBackgroundTaskRunner();
+
  private:
   // For testing.
   friend class TestLargeIconService;
 
-  // Resizes |bitmap_result| to |desired_size_in_pixel|x|desired_size_in_pixel|.
-  // Stores the resized bitmap data in |resized_bitmap_result| and returns true
-  // if successful.
-  bool ResizeLargeIconIfValid(
-      int min_source_size_in_pixel,
-      int desired_size_in_pixel,
-      const favicon_base::FaviconRawBitmapResult& bitmap_result,
-      favicon_base::FaviconRawBitmapResult* resized_bitmap_result);
-
-  // Intermediate callback for GetLargeIconOrFallbackStyle(). Tries to resize
-  // |bitmap_result| and pass the output to |callback|. If that does not work,
-  // computes the icon fallback style and uses it to invoke |callback|.
-  void RunLargeIconCallback(
-      const favicon_base::LargeIconCallback& callback,
-      int min_source_size_in_pixel,
-      int desired_size_in_pixel,
-      const favicon_base::FaviconRawBitmapResult& bitmap_result);
-
   FaviconService* favicon_service_;
 
-  // A pre-populated list of the types of icon files to consider when looking
-  // for large icons. This is an optimization over populating an icon type
-  // vector on each request.
+  // A pre-populated list of icon types to consider when looking for large
+  // icons. This is an optimization over populating an icon type vector on each
+  // request.
   std::vector<int> large_icon_types_;
 
   DISALLOW_COPY_AND_ASSIGN(LargeIconService);
 };
 
 }  // namespace favicon
 
 #endif  // COMPONENTS_FAVICON_CORE_LARGE_ICON_SERVICE_H_