Fix __dict__

TBR=epoger
BUG=skia:1329

Review URL: https://codereview.chromium.org/199463002

scripts/run_cmd.py

diff --git a/scripts/run_cmd.py b/scripts/run_cmd.py
index a30d2d5..4a5faa2 100755
--- a/scripts/run_cmd.py
+++ b/scripts/run_cmd.py
@@ -72,7 +72,7 @@
     Since collections.NamedTuple.__dict__ returns an OrderedDict, we have to
     create this wrapper to get a normal dict.
     """
-    return dict(super(CommandResults, self).__dict__)
+    return dict(self._asdict())
 
   def print_results(self, pretty=False):
     """Print the results of a command.