Move enable extensions define to a build flag.

chrome/browser/renderer_context_menu/context_menu_content_type_factory.cc

Index: chrome/browser/renderer_context_menu/context_menu_content_type_factory.cc
diff --git a/chrome/browser/renderer_context_menu/context_menu_content_type_factory.cc b/chrome/browser/renderer_context_menu/context_menu_content_type_factory.cc
index 351ff01692604e2b173de7df1de75ccffa27abf5..f60f25c4ab29bf84c8385f97a132d4a9462e6d93 100644
--- a/chrome/browser/renderer_context_menu/context_menu_content_type_factory.cc
+++ b/chrome/browser/renderer_context_menu/context_menu_content_type_factory.cc
@@ -9,8 +9,9 @@
 #include "components/renderer_context_menu/context_menu_content_type.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/url_constants.h"
+#include "extensions/features/features.h"
 
-#if defined(ENABLE_EXTENSIONS)
+#if BUILDFLAG(ENABLE_EXTENSIONS)
 #include "chrome/browser/app_mode/app_mode_utils.h"
 #include "chrome/browser/guest_view/web_view/context_menu_content_type_web_view.h"
 #include "chrome/browser/renderer_context_menu/context_menu_content_type_app_mode.h"
@@ -57,7 +58,7 @@ ContextMenuContentTypeFactory::SetInternalResourcesURLChecker(
 ContextMenuContentType* ContextMenuContentTypeFactory::CreateInternal(
     content::WebContents* web_contents,
     const content::ContextMenuParams& params) {
-#if defined(ENABLE_EXTENSIONS)
+#if BUILDFLAG(ENABLE_EXTENSIONS)
   if (extensions::WebViewGuest::FromWebContents(web_contents))
     return new ContextMenuContentTypeWebView(web_contents, params);