PlzNavigate: Show error pages when the navigation failed before commit

content/public/test/test_navigation_observer.h

Index: content/public/test/test_navigation_observer.h
diff --git a/content/public/test/test_navigation_observer.h b/content/public/test/test_navigation_observer.h
index 31a94d63f6d2ea2f9fb35e8fbbcf4099550ccd39..9a5f6a3d4b18db695f89c3f0665efb2875866584 100644
--- a/content/public/test/test_navigation_observer.h
+++ b/content/public/test/test_navigation_observer.h
@@ -44,6 +44,8 @@ class TestNavigationObserver {
 
   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);
@@ -83,6 +85,9 @@ class TestNavigationObserver {
   // 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_;