Service CreateNewWindow on the UI thread with a new mojo interface

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 726ecaa63ebc87725dec1264e9dd64ef1aced825..6b969c632c52163b0dc185b8b814c9fb45e6a2e3 100644
--- a/content/renderer/render_frame_impl.h
+++ b/content/renderer/render_frame_impl.h
@@ -321,6 +321,9 @@ class CONTENT_EXPORT RenderFrameImpl
   // blink has a separate accessibility tree per frame.
   void FocusedNodeChangedForAccessibility(const blink::WebNode& node);
 
+  // Virtual to allow for overriding in TestRenderFrame.
+  virtual mojom::FrameHostIPC* GetFrameHostIPC();
+
   // A RenderView opened by this RenderFrame needs to be shown.
   void ShowCreatedWindow(bool opened_by_user_gesture,
                          RenderWidget* render_widget_to_show,
@@ -1379,6 +1382,7 @@ class CONTENT_EXPORT RenderFrameImpl
   mojo::AssociatedBinding<mojom::FrameBindingsControl>
       frame_bindings_control_binding_;
   mojom::FrameHostPtr frame_host_;
+  mojom::FrameHostIPCAssociatedPtr frame_host_ipc_;
 
   // Indicates whether |didAccessInitialDocument| was called.
   bool has_accessed_initial_document_;