PlzNavigate: Show error pages when the navigation failed before commit

content/browser/browser_side_navigation_browsertest.cc

Index: content/browser/browser_side_navigation_browsertest.cc
diff --git a/content/browser/browser_side_navigation_browsertest.cc b/content/browser/browser_side_navigation_browsertest.cc
index 4bba0ee76dd9ff4a14b2d8efa812661ab8df9df6..5c170888197bbc34fea16c203c532ec64ad98f37 100644
--- a/content/browser/browser_side_navigation_browsertest.cc
+++ b/content/browser/browser_side_navigation_browsertest.cc
@@ -159,4 +159,27 @@ IN_PROC_BROWSER_TEST_F(BrowserSideNavigationBrowserTest,
                              ->GetFrameTree()->root()->current_frame_host());
 }
 
+// Ensure that browser side navigation handles navigation failures.
+IN_PROC_BROWSER_TEST_F(BrowserSideNavigationBrowserTest, FailedNavigation) {
+  // Perform a navigation with no live renderer.
+  {
+    TestNavigationObserver observer(shell()->web_contents());
+    GURL url(embedded_test_server()->GetURL("/title1.html"));
+    NavigateToURL(shell(), url);
+    EXPECT_EQ(url, observer.last_navigation_url());
+    EXPECT_TRUE(observer.last_navigation_succeeded());
+  }
+
+  // Now navigate to an unreachable url.
+  {
+    TestNavigationObserver observer(shell()->web_contents());
+    GURL url("http://127.0.0.1:4");

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

The url was chosen to get a network error (otherwise the test server returns a
404 which does not result in a navigation failure).

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

I think we have better ways to do this.  Please see
NavigationControllerBrowserTest.ErrorPageReplacement:

  GURL error_url(
      net::URLRequestFailedJob::GetMockHttpUrl(net::ERR_CONNECTION_RESET));
  net::URLRequestFailedJob::AddUrlHandler();

(I'm not 100% sure how that works, but I think this is what it's for.)

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

Done.

+    NavigateToURL(shell(), url);
+    EXPECT_EQ(url, observer.last_navigation_url());
+    EXPECT_EQ(1, observer.navigations_failed());
+    // TODO(clamy): when start/stop loading events are properly reported, update
+    // this test to check for the status of the last navigation.
+  }
+}
+
 }  // namespace content