Only enable Hotwords when extensions are enabled.

chrome/browser/extensions/external_component_loader.cc

Index: chrome/browser/extensions/external_component_loader.cc
diff --git a/chrome/browser/extensions/external_component_loader.cc b/chrome/browser/extensions/external_component_loader.cc
index 10eb0ec145c2570f7f632cc244533d967576b44e..462ea8b6f37860f382984d1ba5639a5c3725a3d8 100644
--- a/chrome/browser/extensions/external_component_loader.cc
+++ b/chrome/browser/extensions/external_component_loader.cc
@@ -6,11 +6,15 @@
 
 #include "chrome/browser/bookmarks/enhanced_bookmarks_features.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/search/hotword_service_factory.h"
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "components/signin/core/browser/signin_manager.h"
 
+// TODO(thestig): Remove after extensions are disabled on mobile.
+#if defined(ENABLE_EXTENSIONS)
+#include "chrome/browser/search/hotword_service_factory.h"
+#endif
+
 namespace {
 
 bool IsUserSignedin(Profile* profile) {
@@ -34,11 +38,13 @@ void ExternalComponentLoader::StartLoading() {
   prefs_->SetString(appId + ".external_update_url",
                     extension_urls::GetWebstoreUpdateUrl().spec());
 
+#if defined(ENABLE_EXTENSIONS)
   if (HotwordServiceFactory::IsHotwordAllowed(profile_)) {
     std::string hotwordId = extension_misc::kHotwordExtensionId;
     prefs_->SetString(hotwordId + ".external_update_url",
                       extension_urls::GetWebstoreUpdateUrl().spec());
   }
+#endif
 
   UpdateBookmarksExperimentState(
       profile_->GetPrefs(),