Enable webview tag in webui

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 1b0effef18fdab97b0221b2e49f8327ea738895f..a705b827ad617f1caecbccad5a8a0833f85cd370 100644
--- a/extensions/browser/guest_view/guest_view_base.cc
+++ b/extensions/browser/guest_view/guest_view_base.cc
@@ -134,11 +134,12 @@ void GuestViewBase::Init(const std::string& embedder_extension_id,
   int embedder_process_id =
       embedder_web_contents->GetRenderProcessHost()->GetID();
 
+  const GURL& embedder_site_url = embedder_web_contents->GetLastCommittedURL();
   Feature::Availability availability = feature->IsAvailableToContext(
       embedder_extension,
       process_map->GetMostLikelyContextType(embedder_extension,
                                             embedder_process_id),
-      embedder_web_contents->GetLastCommittedURL());
+      embedder_site_url);
   if (!availability.is_available()) {
     callback.Run(NULL);
     return;
@@ -146,6 +147,7 @@ void GuestViewBase::Init(const std::string& embedder_extension_id,
 
   CreateWebContents(embedder_extension_id,
                     embedder_process_id,
+                    embedder_site_url,
                     create_params,
                     base::Bind(&GuestViewBase::CompleteInit,
                                AsWeakPtr(),