Have different text for apps and regular extensions in some more places.

chrome/browser/extensions/crx_installer.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/crx_installer.h"
 
 #include <map>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 452 matching lines @@
 }
 
 void CrxInstaller::CompleteInstall() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
   if (!current_version_.empty()) {
     Version current_version(current_version_);
     if (current_version.CompareTo(*(extension_->version())) > 0) {
       ReportFailureFromFileThread(
           CrxInstallerError(
-              l10n_util::GetStringUTF16(IDS_EXTENSION_CANT_DOWNGRADE_VERSION)));
+              l10n_util::GetStringUTF16(extension_->is_app() ?
+                  IDS_APP_CANT_DOWNGRADE_VERSION :
+                  IDS_EXTENSION_CANT_DOWNGRADE_VERSION)));
       return;
     }
   }
 
   // See how long extension install paths are.  This is important on
   // windows, because file operations may fail if the path to a file
   // exceeds a small constant.  See crbug.com/69693 .
   UMA_HISTOGRAM_CUSTOM_COUNTS(
     "Extensions.CrxInstallDirPathLength",
         install_directory_.value().length(), 0, 500, 100);
@@ skipping 131 matching lines @@
   // is problematic because they don't know anything about the
   // extension before it is unpacked, so they cannot filter based
   // on the extension.
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_CRX_INSTALLER_DONE,
       content::Source<CrxInstaller>(this),
       content::Details<const Extension>(extension));
 }
 
 }  // namespace extensions