[telemetry] Change many relative paths to use util.Get*Dir().

tools/telemetry/telemetry/core/browser_unittest.py

Index: tools/telemetry/telemetry/core/browser_unittest.py
diff --git a/tools/telemetry/telemetry/core/browser_unittest.py b/tools/telemetry/telemetry/core/browser_unittest.py
index 2493b9cccad9a3d0019b3efe6564804fb0ed181f..873edd3520bca3bec50504f059920619bc1c2f27 100644
--- a/tools/telemetry/telemetry/core/browser_unittest.py
+++ b/tools/telemetry/telemetry/core/browser_unittest.py
@@ -2,13 +2,13 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 import logging
-import os
 import unittest
 
 from telemetry.core import browser_finder
 from telemetry.core import gpu_device
 from telemetry.core import gpu_info
 from telemetry.core import system_info
+from telemetry.core import util
 from telemetry.unittest import options_for_unittests
 
 class BrowserTest(unittest.TestCase):
@@ -42,9 +42,7 @@ class BrowserTest(unittest.TestCase):
     self._browser = browser_to_create.Create()
     self._browser.Start()
 
-    unittest_data_dir = os.path.join(os.path.dirname(__file__),
-                                     '..', '..', 'unittest_data')
-    self._browser.SetHTTPServerDirectories(unittest_data_dir)
+    self._browser.SetHTTPServerDirectories(util.GetUnittestDataDir())
 
     return self._browser