Apps on NTP should be in order of installation

chrome/browser/extensions/pending_extension_info.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_PENDING_EXTENSION_INFO_H_
 #define CHROME_BROWSER_EXTENSIONS_PENDING_EXTENSION_INFO_H_
 #pragma once
 
 #include "base/version.h"
 #include "chrome/common/extensions/extension.h"
 #include "googleurl/src/gurl.h"
 
 // A pending extension is an extension that hasn't been installed yet
 // and is intended to be installed in the next auto-update cycle.  The
 // update URL of a pending extension may be blank, in which case a
 // default one is assumed.
 // TODO(skerner): Make this class an implementation detail of
 // PendingExtensionManager, and remove all other users.
 class PendingExtensionInfo {
  public:
   typedef bool (*ShouldAllowInstallPredicate)(const extensions::Extension&);
 
   PendingExtensionInfo(
+      const std::string& id,
       const GURL& update_url,
       const Version& version,
       ShouldAllowInstallPredicate should_allow_install,
       bool is_from_sync,
       bool install_silently,
       extensions::Extension::Location install_source);
 
   // Required for STL container membership.  Should not be used directly.
   PendingExtensionInfo();
 
+  // Consider two PendingExtensionInfos equal if their ids are equal.
+  bool operator==(const PendingExtensionInfo& rhs) const;
+
+  const std::string& id() const { return id_; }
   const GURL& update_url() const { return update_url_; }
   const Version& version() const { return version_; }
 
   // ShouldAllowInstall() returns the result of running constructor argument
   // |should_allow_install| on an extension. After an extension is unpacked,
   // this function is run. If it returns true, the extension is installed.
   // If not, the extension is discarded. This allows creators of
   // PendingExtensionInfo objects to ensure that extensions meet some criteria
   // that can only be tested once the extension is unpacked.
   bool ShouldAllowInstall(const extensions::Extension& extension) const {
     return should_allow_install_(extension);
   }
   bool is_from_sync() const { return is_from_sync_; }
   bool install_silently() const { return install_silently_; }
   extensions::Extension::Location install_source() const {
         return install_source_;
   }
 
  private:
+  std::string id_;
+
   GURL update_url_;
   Version version_;
 
   // When the extension is about to be installed, this function is
   // called.  If this function returns true, the install proceeds.  If
   // this function returns false, the install is aborted.
   ShouldAllowInstallPredicate should_allow_install_;
 
   bool is_from_sync_;  // This update check was initiated from sync.
   bool install_silently_;
   extensions::Extension::Location install_source_;
 
   FRIEND_TEST_ALL_PREFIXES(ExtensionServiceTest, AddPendingExtensionFromSync);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_PENDING_EXTENSION_INFO_H_