Disable flaky LoginPromptBrowserTest.TestCancelAuth_OnNavigation test on Linux ChromeOS

chrome/browser/ui/login/login_handler_browsertest.cc

 // 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.
 
 #include <algorithm>
 #include <list>
 #include <map>
 
 #include "base/metrics/field_trial.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 329 matching lines @@
   auth_needed_waiter.Wait();
   WindowedAuthCancelledObserver auth_cancelled_waiter(controller);
   LoginHandler* handler = *observer.handlers().begin();
   ASSERT_TRUE(handler);
   handler->CancelAuth();
   auth_cancelled_waiter.Wait();
   load_stop_waiter.Wait();
   EXPECT_TRUE(observer.handlers().empty());
 }
 
+// Flaky on linux chromeos bots: crbug.com/648826.
+#if defined(OS_LINUX) && defined(OS_CHROMEOS)
+#define MAYBE_TestCancelAuth_OnNavigation DISABLED_TestCancelAuth_OnNavigation
+#else
+#define MAYBE_TestCancelAuth_OnNavigation TestCancelAuth_OnNavigation
+#endif
 // Test login prompt cancellation on navigation to a new page.
-IN_PROC_BROWSER_TEST_F(LoginPromptBrowserTest, TestCancelAuth_OnNavigation) {
+IN_PROC_BROWSER_TEST_F(LoginPromptBrowserTest,
+                       MAYBE_TestCancelAuth_OnNavigation) {
   ASSERT_TRUE(embedded_test_server()->Start());
   const GURL kAuthURL = embedded_test_server()->GetURL(kAuthBasicPage);
   const GURL kNoAuthURL = embedded_test_server()->GetURL(kNoAuthPage1);
 
   NavigationController* controller =
       &browser()->tab_strip_model()->GetActiveWebContents()->GetController();
 
   LoginPromptBrowserTestObserver observer;
   observer.Register(content::Source<NavigationController>(controller));
 
@@ skipping 1126 matching lines @@
   // out.
   EXPECT_TRUE(
       WaitForRenderFrameReady(contents->GetInterstitialPage()->GetMainFrame()));
   EXPECT_TRUE(contents->ShowingInterstitialPage());
   EXPECT_EQ(SSLBlockingPage::kTypeForTesting, contents->GetInterstitialPage()
                                                   ->GetDelegateForTesting()
                                                   ->GetTypeForTesting());
 }
 
 }  // namespace