Record start up latency of DOM distiller viewer

chrome/browser/dom_distiller/tab_utils.cc

Index: chrome/browser/dom_distiller/tab_utils.cc
diff --git a/chrome/browser/dom_distiller/tab_utils.cc b/chrome/browser/dom_distiller/tab_utils.cc
index 85eac2a9d82c8e571aa0e49ae68b56dd57ee5aaa..00f6e1f31a0c751d7b85f2460243e86378d4ea99 100644
--- a/chrome/browser/dom_distiller/tab_utils.cc
+++ b/chrome/browser/dom_distiller/tab_utils.cc
@@ -106,7 +106,8 @@ void SelfDeletingRequestDelegate::TakeViewerHandle(
 void StartNavigationToDistillerViewer(content::WebContents* web_contents,
                                       const GURL& url) {
   GURL viewer_url = dom_distiller::url_utils::GetDistillerViewUrlFromUrl(
-      dom_distiller::kDomDistillerScheme, url);
+      dom_distiller::kDomDistillerScheme, url,
+      (base::TimeTicks::Now() - base::TimeTicks()).InMilliseconds());

[mdjones, 2016/05/31 17:26:25]

I'm not sure I understand why the subtraction is needed.

[wychen, 2016/05/31 17:59:26]

TimeTicks cannot be directly converted to int. TimeDelta can.

   content::NavigationController::LoadURLParams params(viewer_url);
   params.transition_type = ui::PAGE_TRANSITION_AUTO_BOOKMARK;
   web_contents->GetController().LoadURLWithParams(params);