Refactored-out the code of thumbnaling algorithm from thumbnail_tab_helper.

chrome/browser/thumbnails/thumbnail_service_impl.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_THUMBNAILS_THUMBNAIL_SERVICE_IMPL_H_
 #define CHROME_BROWSER_THUMBNAILS_THUMBNAIL_SERVICE_IMPL_H_
 
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/history/top_sites.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/thumbnails/thumbnail_service.h"
 
 namespace base {
 class RefCountedMemory;
 }
 
 namespace thumbnails {
 
 // An implementation of ThumbnailService which delegates storage and most of
 // logic to an underlying TopSites instances.
 class ThumbnailServiceImpl : public ThumbnailService {
  public:
   explicit ThumbnailServiceImpl(Profile* profile);
 
   // Implementation of ThumbnailService.
-  virtual bool SetPageThumbnail(const GURL& url,
-                                const gfx::Image& thumbnail,
-                                const ThumbnailScore& score) OVERRIDE;
+  virtual bool SetPageThumbnail(const ThumbnailingContext& context,
+                                const gfx::Image& thumbnail) OVERRIDE;
+  virtual ThumbnailingAlgorithm* GetThumbnailingAlgorithm() const OVERRIDE;
   virtual bool GetPageThumbnail(
       const GURL& url,
       scoped_refptr<base::RefCountedMemory>* bytes) OVERRIDE;
   virtual bool ShouldAcquirePageThumbnail(const GURL& url) OVERRIDE;
 
   // Implementation of RefcountedProfileKeyedService.
   virtual void ShutdownOnUIThread() OVERRIDE;
 
  private:
   virtual ~ThumbnailServiceImpl();
 
   scoped_refptr<history::TopSites> top_sites_;
 
   DISALLOW_COPY_AND_ASSIGN(ThumbnailServiceImpl);
 };
 
 }
 
 #endif  // CHROME_BROWSER_THUMBNAILS_THUMBNAIL_SERVICE_IMPL_H_