Fix minor issues in video screenshot tests.

Ran tests only on boards we care about, for the rest raise TestNAError

We had splitted our CL to multiple smaller changelists. We fixed issues
in those CLs iteratively.

This CL makes minor fixes so that the whole things works again.

BUG=chromium:363815
TEST=Ran test locally that use the whole code.

Change-Id: I155acb6992f2449c8b20596eb5c83c620da20c76
Reviewed-on: https://chromium-review.googlesource.com/201698
Reviewed-by: Rohit Makasana <rohitbm@chromium.org>
Reviewed-by: Kris Rambish <krisr@chromium.org>
Commit-Queue: Rohit Makasana <rohitbm@chromium.org>
Tested-by: Rohit Makasana <rohitbm@chromium.org>
diff --git a/client/common_lib/file_utils.py b/client/common_lib/file_utils.py
index 602671e..8c9b960 100644
--- a/client/common_lib/file_utils.py
+++ b/client/common_lib/file_utils.py
@@ -17,7 +17,7 @@
     try:
         shutil.rmtree(dir_to_remove)
     except OSError as e:
-        if e.errno != errno.ENONET:
+        if e.errno != errno.ENOENT:
             raise