Enforce the 'requirements' field in manifests.

chrome/browser/ui/webui/ntp/app_launcher_handler.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/ui/webui/ntp/app_launcher_handler.h"
 
 #include <string>
 #include <vector>
 
 #include "base/auto_reset.h"
@@ skipping 800 matching lines @@
                                                &(web_app->icons[0].data))) {
     web_app->icons[0].url = GURL();
     web_app->icons[0].width = web_app->icons[0].data.width();
     web_app->icons[0].height = web_app->icons[0].data.height();
   } else {
     web_app->icons.clear();
   }
 
   scoped_refptr<CrxInstaller> installer(
       CrxInstaller::Create(extension_service_, NULL));
+  installer->set_error_on_unsupported_requirements(true);
   installer->set_page_ordinal(install_info->page_ordinal);
   installer->InstallWebApp(*web_app);
   attempted_bookmark_app_install_ = true;
 }
 
 void AppLauncherHandler::SetAppToBeHighlighted() {
   if (highlight_app_id_.empty())
     return;
 
   StringValue app_id(highlight_app_id_);
@@ skipping 166 matching lines @@
 
 void AppLauncherHandler::UninstallDefaultApps() {
   AppsPromo* apps_promo = extension_service_->apps_promo();
   const extensions::ExtensionIdSet& app_ids = apps_promo->old_default_apps();
   for (extensions::ExtensionIdSet::const_iterator iter = app_ids.begin();
        iter != app_ids.end(); ++iter) {
     if (extension_service_->GetExtensionById(*iter, true))
       extension_service_->UninstallExtension(*iter, false, NULL);
   }
 }