Update CNS to run on chromeperf34 and CNS tests to run on windows perf_av bot.

chrome/test/functional/media/media_seek_perf.py

Index: chrome/test/functional/media/media_seek_perf.py
diff --git a/chrome/test/functional/media/media_seek_perf.py b/chrome/test/functional/media/media_seek_perf.py
index 98210c1ecc03f063e3dd02c8565aa882d03ab594..04d67e198feaacbe4ebfca65702c182d23ee949a 100755
--- a/chrome/test/functional/media/media_seek_perf.py
+++ b/chrome/test/functional/media/media_seek_perf.py
@@ -11,6 +11,7 @@ different network constraints.
 
 import logging
 import os
+import posixpath
 
 import pyauto_media
 import pyauto_utils
@@ -26,10 +27,10 @@ _TEST_HTML_PATH = os.path.join('media', 'html', 'media_seek.html')
 
 # The media files used for testing.
 # Path under CNS root folder (pyauto_private/media).
-_TEST_VIDEOS = [os.path.join('dartmoor', name) for name in
+_TEST_VIDEOS = [posixpath.join('dartmoor', name) for name in
                 ['dartmoor2.ogg', 'dartmoor2.m4a', 'dartmoor2.mp3',
                  'dartmoor2.wav']]
-_TEST_VIDEOS.extend(os.path.join('crowd', name) for name in
+_TEST_VIDEOS.extend(posixpath.join('crowd', name) for name in
                     ['crowd1080.webm', 'crowd1080.ogv', 'crowd1080.mp4',
                      'crowd360.webm', 'crowd360.ogv', 'crowd360.mp4'])