Improve syncing between dom distiller and the print preview request

chrome/browser/dom_distiller/lazy_dom_distiller_service.cc

Index: chrome/browser/dom_distiller/lazy_dom_distiller_service.cc
diff --git a/chrome/browser/dom_distiller/lazy_dom_distiller_service.cc b/chrome/browser/dom_distiller/lazy_dom_distiller_service.cc
index eefec74874803a533394554f317cbe703d33ed98..6a7b9fe5dc3015217dc54a797eeb1114aa4a0a78 100644
--- a/chrome/browser/dom_distiller/lazy_dom_distiller_service.cc
+++ b/chrome/browser/dom_distiller/lazy_dom_distiller_service.cc
@@ -86,6 +86,12 @@ scoped_ptr<ViewerHandle> LazyDomDistillerService::ViewUrl(
   return instance()->ViewUrl(delegate, std::move(distiller_page), url);
 }
 
+scoped_ptr<ViewerHandle> LazyDomDistillerService::AddViewRequestDelegate(
+    ViewRequestDelegate* delegate,
+    const GURL& url) {
+  return instance()->AddViewRequestDelegate(delegate, url);
+}
+
 scoped_ptr<DistillerPage>
 LazyDomDistillerService::CreateDefaultDistillerPage(
     const gfx::Size& render_view_size) {