Check that playerStatus is defined.

BUG=None
TEST=trybot

Change-Id: I821fd9008c7ed1d3134c01cf08861fa403ee3832
Previous-Reviewed-on: https://chromium-review.googlesource.com/187184
(cherry picked from commit 50c280f4fb96a31211c2f5eabe788be202140e9e)
Reviewed-on: https://chromium-review.googlesource.com/187495
Reviewed-by: Rohit Makasana <rohitbm@chromium.org>
Commit-Queue: Rohit Makasana <rohitbm@chromium.org>
Tested-by: Rohit Makasana <rohitbm@chromium.org>
diff --git a/client/cros/video/youtube_helper.py b/client/cros/video/youtube_helper.py
index 4085aa4..e859040 100644
--- a/client/cros/video/youtube_helper.py
+++ b/client/cros/video/youtube_helper.py
@@ -54,7 +54,8 @@
     def get_player_status(self):
         """Returns the player status."""
         return self._tab.EvaluateJavaScript(
-                'playerStatus && playerStatus.innerHTML')
+                '(typeof playerStatus !== \'undefined\') && '
+                'playerStatus.innerHTML')
 
 
     def set_playback_quality(self, quality):