Disable BackgroundKeepaliveActive test

chrome/browser/extensions/app_background_page_apitest.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 "base/path_service.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/background/background_contents_service.h"
 #include "chrome/browser/background/background_contents_service_factory.h"
 #include "chrome/browser/background/background_mode_manager.h"
@@ skipping 587 matching lines @@
   UnloadExtensionViaTask(extension->id());
   content::RunAllPendingInMessageLoop();
   ASSERT_TRUE(WaitForBackgroundMode(false));
 }
 
 // Verify active NaCl embeds cause many keepalive impulses to be sent.
 // Disabled on Windows due to flakiness: http://crbug.com/346278
 #if defined(OS_WIN)
 #define MAYBE_BackgroundKeepaliveActive DISABLED_BackgroundKeepaliveActive
 #else
-#define MAYBE_BackgroundKeepaliveActive BackgroundKeepaliveActive
+// Disabling other platforms too since the test started failing
+// consistently. http://crbug.com/490440
+#define MAYBE_BackgroundKeepaliveActive DISABLED_BackgroundKeepaliveActive
 #endif
 IN_PROC_BROWSER_TEST_F(AppBackgroundPageNaClTest,
                        MAYBE_BackgroundKeepaliveActive) {
 #if !defined(DISABLE_NACL)
   ExtensionTestMessageListener nacl_modules_loaded("nacl_modules_loaded", true);
   LaunchTestingApp();
   extensions::ProcessManager* manager =
       extensions::ProcessManager::Get(browser()->profile());
   ImpulseCallbackCounter active_impulse_counter(manager, extension()->id());
   EXPECT_TRUE(nacl_modules_loaded.WaitUntilSatisfied());
@@ skipping 23 matching lines @@
       extensions::ProcessManager::Get(browser()->profile());
   ImpulseCallbackCounter idle_impulse_counter(manager, extension()->id());
   EXPECT_TRUE(nacl_modules_loaded.WaitUntilSatisfied());
 
   manager->SetKeepaliveImpulseDecrementCallbackForTesting(
       idle_impulse_counter.SetGoalAndGetCallback(1));
   nacl_modules_loaded.Reply("be idle");
   idle_impulse_counter.Wait();
 #endif
 }