Update post state on navigation within page.

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 54691513c4e6440fbb327cd921af88d3d5f09d5f..87757126d42a80f2aa1deaeb6010ad340ba1e3b6 100644
--- a/content/browser/frame_host/navigation_controller_impl.cc
+++ b/content/browser/frame_host/navigation_controller_impl.cc
@@ -1168,6 +1168,9 @@ void NavigationControllerImpl::RendererDidNavigateInPage(
   if (existing_entry->update_virtual_url_with_url())
     UpdateVirtualURLToURL(existing_entry, params.url);
 
+  existing_entry->SetHasPostData(params.is_post);
+  existing_entry->SetPostID(params.post_id);
+
   // This replaces the existing entry since the page ID didn't change.
   *did_replace_entry = true;