Apps on NTP should be in order of installation

chrome/browser/extensions/updater/extension_updater.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_EXTENSIONS_UPDATER_EXTENSION_UPDATER_H_
 #define CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_UPDATER_H_
 #pragma once
 
-#include <set>
+#include <list>
 #include <stack>
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/file_path.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time.h"
 #include "base/timer.h"
@@ skipping 86 matching lines @@
 
   // Sets the timer to call TimerFired after roughly |target_delay| from now.
   // To help spread load evenly on servers, this method adds some random
   // jitter. It also saves the scheduled time so it can be reloaded on
   // browser restart.
   void ScheduleNextCheck(const base::TimeDelta& target_delay);
 
   // Add fetch records for extensions that are installed to the downloader,
   // ignoring |pending_ids| so the extension isn't fetched again.
   void AddToDownloader(const ExtensionSet* extensions,
-                       const std::set<std::string>& pending_ids);
+                       const std::list<std::string>& pending_ids);
 
   // BaseTimer::ReceiverMethod callback.
   void TimerFired();
 
   // Posted by CheckSoon().
   void DoCheckSoon();
 
   // Implenentation of ExtensionDownloaderDelegate.
   virtual void OnExtensionDownloadFailed(const std::string& id,
                                          Error error,
@@ skipping 50 matching lines @@
   base::OneShotTimer<ExtensionUpdater> timer_;
   int frequency_seconds_;
   bool will_check_soon_;
 
   ExtensionPrefs* extension_prefs_;
   PrefService* prefs_;
   Profile* profile_;
   bool blacklist_checks_enabled_;
 
   // The ids of extensions that have in-progress update checks.
-  std::set<std::string> in_progress_ids_;
+  std::list<std::string> in_progress_ids_;
 
   // Observes CRX installs we initiate.
   content::NotificationRegistrar registrar_;
 
   // True when a CrxInstaller is doing an install.  Used in MaybeUpdateCrxFile()
   // to keep more than one install from running at once.
   bool crx_install_is_running_;
 
   // Fetched CRX files waiting to be installed.
   std::stack<FetchedCRXFile> fetched_crx_files_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionUpdater);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_UPDATER_H_