Change GuestViewInternalCreateGuestFunction to create the guest view using the

extensions/browser/guest_view/guest_view_base.cc

Index: extensions/browser/guest_view/guest_view_base.cc
diff --git a/extensions/browser/guest_view/guest_view_base.cc b/extensions/browser/guest_view/guest_view_base.cc
index 60e1b3cfd14ba585cb77b1f955ece1f4e014332a..d0469cada0823a381f4ec58cea3bc30abc63ca9d 100644
--- a/extensions/browser/guest_view/guest_view_base.cc
+++ b/extensions/browser/guest_view/guest_view_base.cc
@@ -121,6 +121,9 @@ void GuestViewBase::Init(const std::string& embedder_extension_id,
       extensions::ExtensionRegistry::Get(browser_context_)
           ->enabled_extensions()
           .GetByID(embedder_extension_id);
+  // Ok for |embedder_extension| to be NULL, the embedder might be WebUI.
+
+  CHECK(embedder_web_contents);
   int embedder_process_id =
       embedder_web_contents->GetRenderProcessHost()->GetID();