SharedWorker: Clarify that SharedWorkerRepository is owned by RenderFrameImpl

content/renderer/render_frame_impl.h

Index: content/renderer/render_frame_impl.h
diff --git a/content/renderer/render_frame_impl.h b/content/renderer/render_frame_impl.h
index 6b25d8e217a59118c75b60306a5701605d0b4c29..6ae3cba3dd51ce533c1d502ef1675c1d43584b51 100644
--- a/content/renderer/render_frame_impl.h
+++ b/content/renderer/render_frame_impl.h
@@ -149,6 +149,7 @@ class RenderWidget;
 class RenderWidgetFullscreenPepper;
 class ResourceRequestBodyImpl;
 class ScreenOrientationDispatcher;
+class SharedWorkerRepository;
 class UserMediaClientImpl;
 struct CommonNavigationParams;
 struct CustomContextMenuContext;
@@ -1321,6 +1322,7 @@ class CONTENT_EXPORT RenderFrameImpl
 #endif
 
   std::unique_ptr<FrameBlameContext> blame_context_;
+  std::unique_ptr<SharedWorkerRepository> shared_worker_repository_;
 
   // Plugins -------------------------------------------------------------------
 #if BUILDFLAG(ENABLE_PLUGINS)