Ensure that favicons always have 1x representation regardless of whether the platform supports it

chrome/browser/favicon/favicon_service.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_FAVICON_FAVICON_SERVICE_H_
 #define CHROME_BROWSER_FAVICON_FAVICON_SERVICE_H_
 
 #include <vector>
 
 #include "base/callback.h"
@@ skipping 38 matching lines @@
     GURL page_url;
     int icon_types;
     int desired_size_in_dip;
     CancelableRequestConsumerBase* consumer;
   };
 
   // Callback for GetFaviconImage() and GetFaviconImageForURL().
   // |FaviconImageResult::image| is constructed from the bitmaps for the
   // passed in URL and icon types which most which closely match the passed in
   // |desired_size_in_dip| at the scale factors supported by the current
-  // platform (eg MacOS).
+  // platform (eg MacOS) in addition to 1x.
   // |FaviconImageResult::icon_url| is the favicon that the favicon bitmaps in
   // |image| originate from.
   // TODO(pkotwicz): Enable constructing |image| from bitmaps from several
   // icon URLs.
   typedef base::Callback<void(Handle, const history::FaviconImageResult&)>
       FaviconImageCallback;
 
   // Callback for GetRawFavicon() and GetRawFaviconForURL().
   // FaviconBitmapResult::bitmap_data is the bitmap in the thumbnail database
   // for the passed in URL and icon types whose pixel size best matches the
   // passed in |desired_size_in_dip| and |desired_scale_factor|. Returns an
   // invalid history::FaviconBitmapResult if there are no matches.
   typedef base::Callback<void(Handle, const history::FaviconBitmapResult&)>
       FaviconRawCallback;
 
   // Callback for GetFavicon() and GetFaviconForURL().
   //
   // The second argument is the set of bitmaps for the passed in URL and
   // icon types whose pixel sizes best match the passed in
-  // |desired_size_in_dip| and |desired_scale_factors|. The vector has at most
-  // one result for each of |desired_scale_factors|. There are less entries if
-  // a single result is the best bitmap to use for several scale factors.
+  // |desired_size_in_dip| at the scale factors supported by the current
+  // platform (eg MacOS) in addition to 1x. The vector has at most one result
+  // for each of the scale factors. There are less entries if a single result
+  // is the best bitmap to use for several scale factors.
   //
   // Third argument:
   // a) If the callback is called as a result of GetFaviconForURL():
   //    The third argument is a map of the icon URLs mapped to |page_url| to
   //    the sizes at which the favicon is available from the web.
   // b) If the callback is called as a result of GetFavicon() or
   //    UpdateFaviconMappingsAndFetch():
   //    The third argument is a map of the subset of |icon_urls| known to the
   //    history backend to a vector of sizes of the favicon bitmaps at each
   //    URL. If none of |icon_urls| are known to the history backend, an empty
@@ skipping 24 matching lines @@
   Handle GetRawFavicon(const GURL& icon_url,
                        history::IconType icon_type,
                        int desired_size_in_dip,
                        ui::ScaleFactor desired_scale_factor,
                        CancelableRequestConsumerBase* consumer,
                        const FaviconRawCallback& callback);
 
   Handle GetFavicon(const GURL& icon_url,
                     history::IconType icon_type,
                     int desired_size_in_dip,
-                    const std::vector<ui::ScaleFactor>& desired_scale_factors,
                     CancelableRequestConsumerBase* consumer,
                     const FaviconResultsCallback& callback);
 
   // Set the favicon mappings to |page_url| for |icon_types| in the history
   // database.
   // Sample |icon_urls|:
   //  { ICON_URL1 -> TOUCH_ICON, known to the database,
   //    ICON_URL2 -> TOUCH_ICON, not known to the database,
   //    ICON_URL3 -> TOUCH_PRECOMPOSED_ICON, known to the database }
   // The new mappings are computed from |icon_urls| with these rules:
   // 1) Any urls in |icon_urls| which are not already known to the database are
   //    rejected.
   //    Sample new mappings to |page_url|: { ICON_URL1, ICON_URL3 }
   // 2) If |icon_types| has multiple types, the mappings are only set for the
   //    largest icon type.
   //    Sample new mappings to |page_url|: { ICON_URL3 }
   // |icon_types| can only have multiple IconTypes if
   // |icon_types| == TOUCH_ICON | TOUCH_PRECOMPOSED_ICON.
   // The favicon bitmaps which most closely match |desired_size_in_dip|
-  // and |desired_scale_factors| from the favicons which were just mapped
-  // to |page_url| are returned. If |desired_size_in_dip| is 0, the
-  // largest favicon bitmap is returned.
+  // at the scale factors supported by the current platform (eg MacOS) in
+  // addition to 1x from the favicons which were just mapped to |page_url| are
+  // returned. If |desired_size_in_dip| is 0, the largest favicon bitmap is
+  // returned.
   Handle UpdateFaviconMappingsAndFetch(
       const GURL& page_url,
       const std::vector<GURL>& icon_urls,
       int icon_types,
       int desired_size_in_dip,
-      const std::vector<ui::ScaleFactor>& desired_scale_factors,
       CancelableRequestConsumerBase* consumer,
       const FaviconResultsCallback& callback);
 
   // Requests the favicons of any of |icon_types| whose pixel sizes most
   // closely match |desired_size_in_dip| and desired scale factors for a web
   // page URL. If |desired_size_in_dip| is 0, the largest favicon for the web
   // page URL is returned. |consumer| is notified when the bits have been
   // fetched. |icon_types| can be any combination of IconType value, but only
   // one icon will be returned in the priority of TOUCH_PRECOMPOSED_ICON,
   // TOUCH_ICON and FAVICON. Each of the three methods below differs in the
   // format of the callback and the requested scale factors. All of the scale
   // factors supported by the current platform (eg MacOS) are requested for
   // GetFaviconImageForURL().
   Handle GetFaviconImageForURL(const FaviconForURLParams& params,
                                const FaviconImageCallback& callback);
 
   Handle GetRawFaviconForURL(const FaviconForURLParams& params,
                              ui::ScaleFactor desired_scale_factor,
                              const FaviconRawCallback& callback);
 
   Handle GetFaviconForURL(
       const FaviconForURLParams& params,
-      const std::vector<ui::ScaleFactor>& desired_scale_factors,
       const FaviconResultsCallback& callback);
 
   // Used to request a bitmap for the favicon with |favicon_id| which is not
   // resized from the size it is stored at in the database. If there are
   // multiple favicon bitmaps for |favicon_id|, the largest favicon bitmap is
   // returned.
   Handle GetLargestRawFaviconForID(history::FaviconID favicon_id,
                                    CancelableRequestConsumerBase* consumer,
                                    const FaviconRawCallback& callback);
 
@@ skipping 76 matching lines @@
       ui::ScaleFactor desired_scale_factor,
       FaviconRawCallback callback,
       Handle handle,
       std::vector<history::FaviconBitmapResult> favicon_bitmap_results,
       history::IconURLSizesMap icon_url_sizes_map);
 
   DISALLOW_COPY_AND_ASSIGN(FaviconService);
 };
 
 #endif  // CHROME_BROWSER_FAVICON_FAVICON_SERVICE_H_