Remove extension group from DOMWrapperWorld.

components/translate/content/renderer/translate_helper.h

Index: components/translate/content/renderer/translate_helper.h
diff --git a/components/translate/content/renderer/translate_helper.h b/components/translate/content/renderer/translate_helper.h
index cdb3f2daff8f6eb9e885eb105d7fdba2fdd0e34e..135d015b640e610e59a4c380240b7cded9fdb9c9 100644
--- a/components/translate/content/renderer/translate_helper.h
+++ b/components/translate/content/renderer/translate_helper.h
@@ -31,7 +31,6 @@ class TranslateHelper : public content::RenderFrameObserver,
  public:
   TranslateHelper(content::RenderFrame* render_frame,
                   int world_id,
-                  int extension_group,
                   const std::string& extension_scheme);
   ~TranslateHelper() override;
 
@@ -145,9 +144,6 @@ class TranslateHelper : public content::RenderFrameObserver,
   // The world ID to use for script execution.
   int world_id_;
 
-  // The extension group.
-  int extension_group_;
-
   // The URL scheme for translate extensions.
   std::string extension_scheme_;