Various logical fixes for jumplist

chrome/browser/win/jumplist.cc

 // Copyright 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.
 
 #include "chrome/browser/win/jumplist.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 178 matching lines @@
     return true;
 
   JumpListUpdater jumplist_updater(app_id);
   if (!jumplist_updater.BeginUpdate())
     return false;
 
   // We allocate 60% of the given JumpList slots to "most-visited" items
   // and 40% to "recently-closed" items, respectively.
   // Nevertheless, if there are not so many items in |recently_closed_pages|,
   // we give the remaining slots to "most-visited" items.
+  // The default maximum number of items to display in JumpList is 10.
+  // https://msdn.microsoft.com/en-us/library/windows/desktop/dd378398(v=vs.85).aspx
   const int kMostVisited = 60;
   const int kRecentlyClosed = 40;
   const int kTotal = kMostVisited + kRecentlyClosed;
   size_t most_visited_items =
       MulDiv(jumplist_updater.user_max_items(), kMostVisited, kTotal);
   size_t recently_closed_items =
       jumplist_updater.user_max_items() - most_visited_items;
   if (recently_closed_pages.size() < recently_closed_items) {
     most_visited_items += recently_closed_items - recently_closed_pages.size();
     recently_closed_items = recently_closed_pages.size();
   }
 
+  // Delete the content in JumpListIcons folder and log the results to UMA.
+  DeleteDirectoryContentAndLogResults(icon_dir, kFileDeleteLimit);
+
   // If JumpListIcons directory doesn't exist (we have tried to create it
   // already) or is not empty, skip updating the jumplist icons. The jumplist
   // links should be updated anyway, as it doesn't involve disk IO. In this
   // case, Chrome's icon will be used for the new links.
 
   if (base::DirectoryExists(icon_dir) && base::IsDirectoryEmpty(icon_dir)) {
     // TODO(chengx): Remove this UMA metric after fixing http://crbug.com/40407.
     UMA_HISTOGRAM_COUNTS_100(
         "WinJumplist.CreateIconFilesCount",
         most_visited_pages.size() + recently_closed_pages.size());
@@ skipping 49 matching lines @@
     // Make sure we are not out of date: if icon_urls_ is not empty, then
     // another notification has been received since we processed this one
     if (!data->icon_urls_.empty())
       return;
 
     // Make local copies of lists so we can release the lock.
     local_most_visited_pages = data->most_visited_pages_;
     local_recently_closed_pages = data->recently_closed_pages_;
   }
 
-  // Delete the content in JumpListIcons folder and log the results to UMA.
-  DeleteDirectoryContentAndLogResults(icon_dir, kFileDeleteLimit);
-
   // Create a new JumpList and replace the current JumpList with it. The
   // jumplist links are updated anyway, while the jumplist icons may not as
   // mentioned above.
   UpdateJumpList(app_id.c_str(), icon_dir, local_most_visited_pages,
                  local_recently_closed_pages, incognito_availability);
 }
 
 }  // namespace
 
 JumpList::JumpListData::JumpListData() {}
@@ skipping 334 matching lines @@
 void JumpList::TopSitesLoaded(history::TopSites* top_sites) {
 }
 
 void JumpList::TopSitesChanged(history::TopSites* top_sites,
                                ChangeReason change_reason) {
   top_sites->GetMostVisitedURLs(
       base::Bind(&JumpList::OnMostVisitedURLsAvailable,
                  weak_ptr_factory_.GetWeakPtr()),
       false);
 }