Remove hotword installation code at compile time if hotwording disabled.

chrome/browser/extensions/external_component_loader.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/external_component_loader.h"
 
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"
 #include "chrome/browser/bookmarks/enhanced_bookmarks_features.h"
 #include "chrome/browser/browser_process.h"
@@ skipping 36 matching lines @@
     return SimpleFeature::IsIdInArray(
         extension->id(), kEnhancedExtensions, arraysize(kEnhancedExtensions));
   }
   return false;
 }
 
 void ExternalComponentLoader::StartLoading() {
   prefs_.reset(new base::DictionaryValue());
   AddExternalExtension(extension_misc::kInAppPaymentsSupportAppId);
 
+#if defined(ENABLE_HOTWORDING)
   if (HotwordServiceFactory::IsHotwordAllowed(profile_))
     AddExternalExtension(extension_misc::kHotwordSharedModuleId);
+#endif  // defined(ENABLE_HOTWORDING)
 
   {
     std::string extension_id;
     if (IsEnhancedBookmarksEnabled(&extension_id))
       AddExternalExtension(extension_id);
   }
 
 #if defined(OS_CHROMEOS)
   {
     base::CommandLine* const command_line =
@@ skipping 21 matching lines @@
 void ExternalComponentLoader::AddExternalExtension(
     const std::string& extension_id) {
   if (!IsComponentExtensionWhitelisted(extension_id))
     return;
 
   prefs_->SetString(extension_id + ".external_update_url",
                     extension_urls::GetWebstoreUpdateUrl().spec());
 }
 
 }  // namespace extensions