MD History: Get sign in state from backend when refreshing the page

chrome/browser/ui/webui/md_history_ui.cc

Index: chrome/browser/ui/webui/md_history_ui.cc
diff --git a/chrome/browser/ui/webui/md_history_ui.cc b/chrome/browser/ui/webui/md_history_ui.cc
index d9f836c7d7b6888212d79f854bd9957f3db81016..ceaaaa27e30ea7c198e59122b2048fadd9f2b401 100644
--- a/chrome/browser/ui/webui/md_history_ui.cc
+++ b/chrome/browser/ui/webui/md_history_ui.cc
@@ -103,12 +103,6 @@ content::WebUIDataSource* CreateMdHistoryUIHTMLSource(Profile* profile) {
 
   source->AddBoolean("isGuestSession", profile->IsGuestSession());
 
-  SigninManagerBase* signin_manager =
-      SigninManagerFactory::GetForProfile(profile);
-  bool is_authenticated = signin_manager != nullptr &&
-      signin_manager->IsAuthenticated();
-  source->AddBoolean("isUserSignedIn", is_authenticated);
-
   source->AddResourcePath("app.html", IDR_MD_HISTORY_APP_HTML);
   source->AddResourcePath("app.js", IDR_MD_HISTORY_APP_JS);
   source->AddResourcePath("browser_service.html",