Made it possible to tell whether an extension is being installed or updated.

chrome/browser/extensions/updater/extension_updater.cc

 // 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.
 
 #include "chrome/browser/extensions/updater/extension_updater.h"
 
 #include <algorithm>
 #include <set>
 #include <vector>
 
@@ skipping 647 matching lines @@
         request.in_progress_ids_.remove(crx_file.extension_id);
         NotifyIfFinished(*it);
       }
 
       // If any files are available to update, start one.
       MaybeInstallCRXFile();
       break;
     }
     case chrome::NOTIFICATION_EXTENSION_INSTALLED: {
       const Extension* extension =
-          content::Details<const Extension>(details).ptr();
+          content::Details<const InstalledExtensionInfo>(details)->extension;
       if (extension)
         throttle_info_.erase(extension->id());
       break;
     }
     default:
       NOTREACHED();
   }
 }
 
 void ExtensionUpdater::NotifyStarted() {
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_EXTENSION_UPDATING_STARTED,
       content::Source<Profile>(profile_),
       content::NotificationService::NoDetails());
 }
 
 void ExtensionUpdater::NotifyIfFinished(int request_id) {
   DCHECK(ContainsKey(requests_in_progress_, request_id));
   const InProgressCheck& request = requests_in_progress_[request_id];
   if (request.in_progress_ids_.empty()) {
     VLOG(2) << "Finished update check " << request_id;
     if (!request.callback.is_null())
       request.callback.Run();
     requests_in_progress_.erase(request_id);
   }
 }
 
 }  // namespace extensions