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 759 matching lines @@
   if (!image_result.image.IsEmpty()) {
     WebApplicationInfo::IconInfo icon;
     icon.data = image_result.image.AsBitmap();
     icon.width = icon.data.width();
     icon.height = icon.data.height();
     web_app->icons.push_back(icon);
   }
 
   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 150 matching lines @@
 
 ExtensionInstallPrompt* AppLauncherHandler::GetExtensionInstallPrompt() {
   if (!extension_install_ui_.get()) {
     Browser* browser = browser::FindBrowserWithWebContents(
         web_ui()->GetWebContents());
     extension_install_ui_.reset(
         chrome::CreateExtensionInstallPromptWithBrowser(browser));
   }
   return extension_install_ui_.get();
 }