Make Uri.base work in SkyView

sky/engine/core/script/dom_dart_state.h

Index: sky/engine/core/script/dom_dart_state.h
diff --git a/sky/engine/core/script/dom_dart_state.h b/sky/engine/core/script/dom_dart_state.h
index 5f22b6feabbabfac40fbf042656254f6cb27cf91..f34f5467cd392cb6ccc2da675573ccd2ea940645 100644
--- a/sky/engine/core/script/dom_dart_state.h
+++ b/sky/engine/core/script/dom_dart_state.h
@@ -17,7 +17,7 @@ class LocalDOMWindow;
 
 class DOMDartState : public DartState {
  public:
-  explicit DOMDartState(Document* document);
+  explicit DOMDartState(Document* document, const KURL& url);
   ~DOMDartState() override;
 
   virtual void DidSetIsolate();
@@ -28,6 +28,8 @@ class DOMDartState : public DartState {
   static LocalFrame* CurrentFrame();
   static LocalDOMWindow* CurrentWindow();
 
+  const KURL& url() const { return url_; }
+
   Document* document() const { return document_.get(); }
   DartLoader& loader() const { return *loader_; }
 
@@ -40,6 +42,7 @@ class DOMDartState : public DartState {
 
  private:
   RefPtr<Document> document_;
+  KURL url_;
   OwnPtr<DartLoader> loader_;
 
   DartPersistentValue x_handle_;