Revert of Remove the use of page id from NavController's GetVisibleEntry.

content/browser/frame_host/navigation_controller_impl.cc

Index: content/browser/frame_host/navigation_controller_impl.cc
diff --git a/content/browser/frame_host/navigation_controller_impl.cc b/content/browser/frame_host/navigation_controller_impl.cc
index aad2109f4d577fb5fa854de89e69895f540f2670..f4f184ba42b9889896b76abd0b6682735ed53464 100644
--- a/content/browser/frame_host/navigation_controller_impl.cc
+++ b/content/browser/frame_host/navigation_controller_impl.cc
@@ -446,7 +446,7 @@
   bool safe_to_show_pending =
       pending_entry_ &&
       // Require a new navigation.
-      pending_entry_index_ == -1 &&
+      pending_entry_->GetPageID() == -1 &&
       // Require either browser-initiated or an unmodified new tab.
       (!pending_entry_->is_renderer_initiated() || IsUnmodifiedBlankTab());
 
@@ -455,7 +455,7 @@
   // can script the new tab before it commits.
   if (!safe_to_show_pending &&
       pending_entry_ &&
-      pending_entry_index_ != -1 &&
+      pending_entry_->GetPageID() != -1 &&
       IsInitialNavigation() &&
       !pending_entry_->is_renderer_initiated())
     safe_to_show_pending = true;