Fix Jumplist favicons to have high resolution in HDPI Windows displays

components/favicon/core/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 COMPONENTS_FAVICON_CORE_FAVICON_SERVICE_H_
 #define COMPONENTS_FAVICON_CORE_FAVICON_SERVICE_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/containers/hash_tables.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/task/cancelable_task_tracker.h"
 #include "components/favicon_base/favicon_callback.h"
 #include "components/favicon_base/favicon_types.h"
 #include "components/favicon_base/favicon_usage_data.h"
 #include "components/keyed_service/core/keyed_service.h"
+#include "ui/gfx/favicon_size.h"
 
 class GURL;
 
 namespace history {
 class HistoryService;
 }
 
 namespace favicon {
 
 class FaviconClient;
@@ skipping 55 matching lines @@
       int desired_size_in_dip,
       const favicon_base::FaviconResultsCallback& callback,
       base::CancelableTaskTracker* tracker);
 
   //////////////////////////////////////////////////////////////////////////////
   // Methods to request favicon bitmaps from the history backend for |page_url|.
   // |page_url| is the web page the favicon is associated with.
   // (e.g. <http://www.google.com>)
 
   // Requests the favicon for the page at |page_url| of type
-  // favicon_base::FAVICON and of size gfx::kFaviconSize. The returned
-  // gfx::Image is populated with representations for all of the scale factors
-  // supported by the platform (e.g. MacOS). If data is unavailable for some or
-  // all of the scale factors, the bitmaps with the best matching sizes are
-  // resized.
+  // favicon_base::FAVICON and of size |faviconSize|. gfx::kFaviconSize is used
+  // by default for |faviconSize|, while gfx::kHdpiFaviconSize should be used
+  // for high DPI machines or displays. The returned gfx::Image is populated
+  // with representations for all of the scale factors supported by the platform
+  // (e.g. MacOS). If data is unavailable for some or all of the scale factors,
+  // the bitmaps with the best matching sizes are resized.
   base::CancelableTaskTracker::TaskId GetFaviconImageForPageURL(
       const GURL& page_url,
       const favicon_base::FaviconImageCallback& callback,
-      base::CancelableTaskTracker* tracker);
+      base::CancelableTaskTracker* tracker,
+      const int faviconSize = gfx::kFaviconSize);

[sky, 2017/01/31 23:28:44]

You shouldn't need to specify a size. The gfx::Image will contain multiple
images if possible so that you can grab the one appropriate based on the scale.

[chengx, 2017/02/02 20:52:58]

Acknowledged.

 
   // Requests the favicon for the page at |page_url| with one of |icon_types|
   // and with |desired_size_in_pixel|. |icon_types| can be any combination of
   // IconTypes. If favicon bitmaps for several IconTypes are available, the
   // favicon bitmap is chosen in the priority of TOUCH_PRECOMPOSED_ICON,
   // TOUCH_ICON and FAVICON. If there is no favicon bitmap of size
   // |desired_size_in_pixel|, the favicon bitmap which best matches
   // |desired_size_in_pixel| is resized. If |desired_size_in_pixel| is 0,
   // the largest favicon bitmap is returned. Results with a higher priority
   // IconType are preferred over an exact match of the favicon bitmap size.
@@ skipping 131 matching lines @@
   base::hash_set<MissingFaviconURLHash> missing_favicon_urls_;
   std::unique_ptr<FaviconClient> favicon_client_;
   history::HistoryService* history_service_;
 
   DISALLOW_COPY_AND_ASSIGN(FaviconService);
 };
 
 }  // namespace favicon
 
 #endif  // COMPONENTS_FAVICON_CORE_FAVICON_SERVICE_H_