Mark error pages as such on Ctrl-Shift-T reload.

content/browser/frame_host/navigation_controller_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/frame_host/navigation_controller_impl.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
@@ skipping 1108 matching lines @@
   // This is a back/forward navigation. The existing page for the ID is
   // guaranteed to exist by ClassifyNavigation, and we just need to update it
   // with new information from the renderer.
   int entry_index = GetEntryIndexWithPageID(rfh->GetSiteInstance(),
                                             params.page_id);
   DCHECK(entry_index >= 0 &&
          entry_index < static_cast<int>(entries_.size()));
   NavigationEntryImpl* entry = entries_[entry_index].get();
 
   // The URL may have changed due to redirects.
+  if (params.url_is_unreachable)
+    entry->set_page_type(PAGE_TYPE_ERROR);
   entry->SetURL(params.url);
   entry->SetReferrer(params.referrer);
   if (entry->update_virtual_url_with_url())
     UpdateVirtualURLToURL(entry, params.url);
 
   // The redirected to page should not inherit the favicon from the previous
   // page.
   if (ui::PageTransitionIsRedirect(params.transition))
     entry->GetFavicon() = FaviconStatus();
 
@@ skipping 32 matching lines @@
   // ClassifyNavigation. All we need to do is update the existing entry.
   NavigationEntryImpl* existing_entry = GetEntryWithPageID(
       rfh->GetSiteInstance(), params.page_id);
 
   // We assign the entry's unique ID to be that of the new one. Since this is
   // always the result of a user action, we want to dismiss infobars, etc. like
   // a regular user-initiated navigation.
   existing_entry->set_unique_id(pending_entry_->GetUniqueID());
 
   // The URL may have changed due to redirects.
+  if (params.url_is_unreachable)
+    existing_entry->set_page_type(PAGE_TYPE_ERROR);
   if (existing_entry->update_virtual_url_with_url())
     UpdateVirtualURLToURL(existing_entry, params.url);
   existing_entry->SetURL(params.url);
   existing_entry->SetReferrer(params.referrer);
 
   // The page may have been requested with a different HTTP method.
   existing_entry->SetHasPostData(params.is_post);
   existing_entry->SetPostID(params.post_id);
 
   DiscardNonCommittedEntries();
 }
 
 void NavigationControllerImpl::RendererDidNavigateInPage(
     RenderFrameHost* rfh,
     const FrameHostMsg_DidCommitProvisionalLoad_Params& params,
     bool* did_replace_entry) {
   DCHECK(ui::PageTransitionIsMainFrame(params.transition)) <<
       "WebKit should only tell us about in-page navs for the main frame.";
   // We're guaranteed to have an entry for this one.
   NavigationEntryImpl* existing_entry = GetEntryWithPageID(
       rfh->GetSiteInstance(), params.page_id);
 
   // Reference fragment navigation. We're guaranteed to have the last_committed
   // entry and it will be the same page as the new navigation (minus the
   // reference fragments, of course).  We'll update the URL of the existing
   // entry without pruning the forward history.
+  // TODO(wjmaclean): do we need an else-clause here to clear the entry, since
+  // it is persisted between navigations?

[Charlie Reis, 2015/02/18 01:01:53]

This is a good question.  Can you test this manually?  I'd suggest navigating to
two pages, disabling your network, clearing cache, then going back.  That should
give you an existing entry with an error page.  Then repeat with the network
re-enabled.  I bet you're right that we would need to fix the page type to be
normal again (in all cases, not just this one).

[wjmaclean, 2015/02/18 19:10:11]

After a manual test, there doesn't seem to be a difference, though in a way I'm
not surprised given how few locations in the code test for PAGE_TYPE_ERROR. But,
I suspect it's the right thing to do, and so have added it in.

[Charlie Reis, 2015/02/18 23:53:04]

I think that's the right thing to do.  Thanks for being thorough!

+  if (params.url_is_unreachable)
+    existing_entry->set_page_type(PAGE_TYPE_ERROR);
   existing_entry->SetURL(params.url);
   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;
 
@@ skipping 573 matching lines @@
     }
   }
 }
 
 void NavigationControllerImpl::SetGetTimestampCallbackForTest(
     const base::Callback<base::Time()>& get_timestamp_callback) {
   get_timestamp_callback_ = get_timestamp_callback;
 }
 
 }  // namespace content