Fix navigation to unittest files

tools/telemetry/telemetry/page/actions/wait_unittest.py

 # 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.
 
 import time
 
 from telemetry.core import util
 from telemetry.page.actions import wait
 from telemetry.unittest import tab_test_case
-from telemetry.unittest import test
 
 
 class WaitActionTest(tab_test_case.TabTestCase):
-  @test.Disabled('chromeos')
   def testWaitAction(self):
-    self._browser.SetHTTPServerDirectories(util.GetUnittestDataDir())
-    self._tab.Navigate(
-      self._browser.http_server.UrlOf('blank.html'))
-    self._tab.WaitForDocumentReadyStateToBeComplete()
+    self.Navigate('blank.html')
     self.assertEquals(
         self._tab.EvaluateJavaScript('document.location.pathname;'),
         '/blank.html')
 
     i = wait.WaitAction({ 'condition': 'duration', 'seconds': 1 })
 
     start_time = time.time()
     i.RunAction(None, self._tab, None)
     self.assertTrue(time.time() - start_time >= 1.0)
 
   def testWaitActionTimeout(self):
     wait_action = wait.WaitAction({
       'condition': 'javascript',
       'javascript': '1 + 1 === 3',
       'timeout': 1
     })
 
     start_time = time.time()
     self.assertRaises(
         util.TimeoutException,
         lambda: wait_action.RunAction(None, self._tab, None))
     self.assertTrue(time.time() - start_time < 5)