Re-enable NewTabUIStartupTest.PerfRefWarm on Linux. Roll to a new

chrome/test/startup/feature_startup_test.cc

 // Copyright (c) 2006-2008 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/file_util.h"
 #include "base/gfx/rect.h"
 #include "base/path_service.h"
 #include "base/perftimer.h"
 #include "base/string_util.h"
 #include "base/time.h"
@@ skipping 171 matching lines @@
   RunStartupTest("tab_cold_ref", false /* cold */, true /* important */,
                  UITest::DEFAULT_THEME);
 }
 #endif
 
 TEST_F(NewTabUIStartupTest, PerfCold) {
   RunStartupTest("tab_cold", false /* cold */, true /* important */,
                  UITest::DEFAULT_THEME);
 }
 
-#if defined(OS_WIN)
+#if !defined(OS_MACOSX)
 // TODO(tc): Update the Mac reference build to support
 // WaitForInitialNewTabUILoad.
-// TODO(tc): This is failing on Linux too.
 TEST_F(NewTabUIStartupTest, PerfRefWarm) {
   UseReferenceBuild();
   RunStartupTest("tab_warm_ref", true /* warm */, true /* not important */,
                  UITest::DEFAULT_THEME);
 }
 #endif
 
 TEST_F(NewTabUIStartupTest, PerfWarm) {
   RunStartupTest("tab_warm", true /* warm */, true /* not important */,
                  UITest::DEFAULT_THEME);
@@ skipping 23 matching lines @@
 }
 
 TEST_F(NewTabUIStartupTest, NativeFrameGtkThemeCold) {
   RunStartupTest("tab_custom_frame_gtk_theme_cold", false /* cold */,
                  false /* not important */,
                  UITest::CUSTOM_FRAME_NATIVE_THEME);
 }
 #endif
 
 }  // namespace