void InfoBarManagerImpl::DidFinishNavigation(
    web::WebState* web_state,
    web::NavigationContext* navigation_context) {
  DCHECK_EQ(web_state_, web_state);
  if (navigation_context->HasCommitted()) {
    OnNavigation(CreateNavigationDetails(
        web_state->GetNavigationManager()->GetLastCommittedItem(),
        navigation_context->IsSameDocument()));
  }
}

0x0 implies that either web_state, web_state->GetNavigationManager(), or navigation_context is nullptr.

Eugene, can DidFinishNavigation ever be called with nullptr arguments? 

NavigationContext must never be null and I think that all DidFinishNavigation callbacks assume non-null navigation_context.

Then that implies that something is wrong in CreateNavigationDetails():

infobars::InfoBarDelegate::NavigationDetails CreateNavigationDetails(
    web::NavigationItem* navigation_item,
    bool is_same_document) {
  infobars::InfoBarDelegate::NavigationDetails navigation_details;
  navigation_details.entry_id = navigation_item->GetUniqueID();
  const ui::PageTransition transition = navigation_item->GetTransitionType();
  navigation_details.is_navigation_to_different_page =
      ui::PageTransitionIsMainFrame(transition) && !is_same_document;
  // Default to false, since iOS callbacks do not specify if navigation was a    
  // repace state navigation .                                                   
  navigation_details.did_replace_entry = false;
  navigation_details.is_reload =
      ui::PageTransitionCoreTypeIs(transition, ui::PAGE_TRANSITION_RELOAD);
  navigation_details.is_redirect = ui::PageTransitionIsRedirect(transition);

  return navigation_details;
}

Probably we have a nullptr |navigation_item|, which means web_state->GetLastCommittedItem() is returning nullptr.  How could that happen, if HasCommitted() is returning true?


@eugene in the code snippet from comment #0, should we be using GetLastCommittedItem(), or should we get the unique id and transition type from the NavigationContext instead?

I believe that web_state->GetLastCommittedItem() should not return null if HasCommitted() returned true. 

We can use transition type from the NavigationContext, but we can't use unique id from the NavigationContext without changing the behavior. It seems like we have a bug with slim navigation manager which we need to fix in ios/web