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

chrome/browser/extensions/extension_service.cc

 // Copyright (c) 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.
 
 #include "chrome/browser/extensions/extension_service.h"
 
 #include <algorithm>
 #include <iterator>
 #include <set>
 
@@ skipping 2405 matching lines @@
   CHECK(extension);
   delayed_updates_for_idle_.Remove(extension_id);
 
   if (!extension_prefs_->FinishDelayedInstallInfo(extension_id))
     NOTREACHED();
 
   FinishInstallation(extension);
 }
 
 void ExtensionService::FinishInstallation(const Extension* extension) {
+  bool is_update = GetInstalledExtension(extension->id()) != NULL;
+  extensions::InstalledExtensionInfo details(extension, is_update);
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_EXTENSION_INSTALLED,
       content::Source<Profile>(profile_),
-      content::Details<const Extension>(extension));
+      content::Details<const extensions::InstalledExtensionInfo>(&details));
 
   bool unacknowledged_external = IsUnacknowledgedExternalExtension(extension);
 
   // Unpacked extensions default to allowing file access, but if that has been
   // overridden, don't reset the value.
   if (Manifest::ShouldAlwaysAllowFileAccess(extension->location()) &&
       !extension_prefs_->HasAllowFileAccessSetting(extension->id())) {
     extension_prefs_->SetAllowFileAccess(extension->id(), true);
   }
 
@@ skipping 665 matching lines @@
 }
 
 void ExtensionService::AddUpdateObserver(extensions::UpdateObserver* observer) {
   update_observers_.AddObserver(observer);
 }
 
 void ExtensionService::RemoveUpdateObserver(
     extensions::UpdateObserver* observer) {
   update_observers_.RemoveObserver(observer);
 }