Fix navigation to unittest files

tools/telemetry/telemetry/page/actions/loop_unittest.py

Index: tools/telemetry/telemetry/page/actions/loop_unittest.py
diff --git a/tools/telemetry/telemetry/page/actions/loop_unittest.py b/tools/telemetry/telemetry/page/actions/loop_unittest.py
index 29ee0f335a2664752192c04071e33b26929a605a..4eee9337e5f7e9e18df2d12571970f28d4c9e691 100644
--- a/tools/telemetry/telemetry/page/actions/loop_unittest.py
+++ b/tools/telemetry/telemetry/page/actions/loop_unittest.py
@@ -5,7 +5,6 @@
 from telemetry.core import util
 from telemetry.page.actions import loop
 from telemetry.unittest import tab_test_case
-from telemetry.unittest import test
 
 AUDIO_1_LOOP_CHECK = 'window.__hasEventCompleted("#audio_1", "loop");'
 VIDEO_1_LOOP_CHECK = 'window.__hasEventCompleted("#video_1", "loop");'
@@ -15,11 +14,8 @@ class LoopActionTest(tab_test_case.TabTestCase):
 
   def setUp(self):
     tab_test_case.TabTestCase.setUp(self)
-    self._browser.SetHTTPServerDirectories(util.GetUnittestDataDir())
-    self._tab.Navigate(self._browser.http_server.UrlOf('video_test.html'))
-    self._tab.WaitForDocumentReadyStateToBeComplete()
+    self.Navigate('video_test.html')
 
-  @test.Disabled('chromeos')
   def testLoopWithNoSelector(self):
     """Tests that with no selector Loop action loops first media element."""
     data = {'selector': '#video_1', 'loop_count': 2}
@@ -30,7 +26,6 @@ class LoopActionTest(tab_test_case.TabTestCase):
     self.assertTrue(self._tab.EvaluateJavaScript(VIDEO_1_LOOP_CHECK))
     self.assertFalse(self._tab.EvaluateJavaScript(AUDIO_1_LOOP_CHECK))
 
-  @test.Disabled('chromeos')
   def testLoopWithAllSelector(self):
     """Tests that Loop action loops all video elements with selector='all'."""
     data = {'selector': 'all', 'loop_count': 2}
@@ -44,7 +39,6 @@ class LoopActionTest(tab_test_case.TabTestCase):
     self.assertTrue(self._tab.EvaluateJavaScript(VIDEO_1_LOOP_CHECK))
     self.assertTrue(self._tab.EvaluateJavaScript(AUDIO_1_LOOP_CHECK))
 
-  @test.Disabled('chromeos')
   def testLoopWaitForLoopTimeout(self):
     """Tests that wait_for_loop timeouts if video does not loop."""
     data = {'selector': '#video_1',