Remove migration of obsolete value for "session.restore_on_startup".

chrome/browser/ui/startup/startup_browser_creator_impl.cc

Index: chrome/browser/ui/startup/startup_browser_creator_impl.cc
diff --git a/chrome/browser/ui/startup/startup_browser_creator_impl.cc b/chrome/browser/ui/startup/startup_browser_creator_impl.cc
index 95cae74a73ecbb497b38a7dc9280880141f7c560..f75fa91a773d52782b5113257696af0f19e9f3a3 100644
--- a/chrome/browser/ui/startup/startup_browser_creator_impl.cc
+++ b/chrome/browser/ui/startup/startup_browser_creator_impl.cc
@@ -681,10 +681,6 @@ Browser* StartupBrowserCreatorImpl::ProcessSpecifiedURLs(
     // specified on the command line. Filter out any urls that are to be
     // restored by virtue of having been previously pinned.
     AddUniqueURLs(pref.urls, &tabs);
-  } else if (pref.type == SessionStartupPref::HOMEPAGE) {
-    // If 'homepage' selected, either by the user or by a policy, we should
-    // have migrated them to another value.
-    NOTREACHED() << "SessionStartupPref has deprecated type HOMEPAGE";
   }
 
   if (tabs.empty())