PlzNavigate: Show error pages when the navigation failed before commit

content/public/test/test_navigation_observer.h

 // Copyright (c) 2012 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.
 
 #ifndef CONTENT_PUBLIC_TEST_TEST_NAVIGATION_OBSERVER_H_
 #define CONTENT_PUBLIC_TEST_TEST_NAVIGATION_OBSERVER_H_
 
 #include <set>
 
 #include "base/callback.h"
@@ skipping 26 matching lines @@
   void Wait();
 
   // Start/stop watching newly created WebContents.
   void StartWatchingNewWebContents();
   void StopWatchingNewWebContents();
 
   const GURL& last_navigation_url() const { return last_navigation_url_; }
 
   int last_navigation_succeeded() const { return last_navigation_succeeded_; }
 
+  int navigations_failed() const { return navigations_failed_; }
+
  protected:
   // Register this TestNavigationObserver as an observer of the |web_contents|.
   void RegisterAsObserver(WebContents* web_contents);
 
  private:
   class TestWebContentsObserver;
 
   // Callbacks for WebContents-related events.
   void OnWebContentsCreated(WebContents* web_contents);
   void OnWebContentsDestroyed(TestWebContentsObserver* observer,
@@ skipping 19 matching lines @@
 
   // If true the navigation has started.
   bool navigation_started_;
 
   // The number of navigations that have been completed.
   int navigations_completed_;
 
   // The number of navigations to wait for.
   int number_of_navigations_;
 
+  // The number of navigations that failed.
+  int navigations_failed_;

[clamy, 2015/04/10 14:04:49]

I had to track the number of navigations that failed since loading the error
page results in a CommitProvisionalLoad message which makes it appear as if the
last navigation succeeded when it did not. This may be due to the fact that
PlzNavigate does not call DidStart/StopLoading properly.

[Charlie Reis, 2015/04/10 22:54:44]

Can you check the page type of the committed NavigationEntry instead?  Something
like this from NavigationControllerBrowserTest.ErrorPageReplacement:

EXPECT_EQ(PAGE_TYPE_ERROR, entry->GetPageType());

That might make changing TestNavigationObserver unnecessary.

[clamy, 2015/04/14 11:56:25]

Done.

+
   // The url of the navigation that last committed.
   GURL last_navigation_url_;
 
   // True if the last navigation succeeded.
   bool last_navigation_succeeded_;
 
   // The MessageLoopRunner used to spin the message loop.
   scoped_refptr<MessageLoopRunner> message_loop_runner_;
 
   // Callback invoked on WebContents creation.
   base::Callback<void(WebContents*)> web_contents_created_callback_;
 
   // Living TestWebContentsObservers created by this observer.
   std::set<TestWebContentsObserver*> web_contents_observers_;
 
   DISALLOW_COPY_AND_ASSIGN(TestNavigationObserver);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_TEST_TEST_NAVIGATION_OBSERVER_H_