Make app list search result mixer more resilient to reordering.

chrome/browser/ui/app_list/search/mixer.h

 // Copyright 2013 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_UI_APP_LIST_SEARCH_MIXER_H_
 #define CHROME_BROWSER_UI_APP_LIST_SEARCH_MIXER_H_
 
 #include "base/basictypes.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_vector.h"
@@ skipping 49 matching lines @@
     bool operator<(const SortData& other) const;
 
     ChromeSearchResult* result;  // Not owned.
     double score;
   };
   typedef std::vector<Mixer::SortData> SortedResults;
 
   class Group;
   typedef ScopedVector<Group> Groups;
 
-  // Publishes the given |results| to |ui_results|. Reuse existing ones to avoid
-  // flickering.
+  // Publishes the given |new_results| to |ui_results|, deleting any existing
+  // results that are not in |new_results|. Results that already exist in
+  // |ui_results| are reused to avoid flickering caused by icon reload.
   static void Publish(const SortedResults& results,
                       AppListModel::SearchResults* ui_results);
 
   // Removes duplicates from |results|.
   static void RemoveDuplicates(SortedResults* results);
 
   void FetchResults(const KnownResults& known_results);
 
   AppListModel::SearchResults* ui_results_;  // Not owned.
   Groups groups_;
 
   DISALLOW_COPY_AND_ASSIGN(Mixer);
 };
 
 }  // namespace app_list
 
 #endif  // CHROME_BROWSER_UI_APP_LIST_SEARCH_MIXER_H_