Fix uninitialized variable error in presubmit_support

Remove 'out' variable reference.  If subprocess.communicate()
throws an exception, out cannot contain data.

BUG=236073
TBR=cmp

Review URL: https://chromiumcodereview.appspot.com/14386022

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@196904 0039d316-1c4b-4281-b951-d872f2087c98

presubmit_support.py

@@ -1299,7 +1299,7 @@ def CallCommand(cmd_data):
       return cmd_data.message('%s failed\n%s' % (cmd_data.name, out))
   except OSError as e:
     return cmd_data.message(
-        '%s exec failure\n   %s\n%s' % (cmd_data.name, e, out))
+        '%s exec failure\n   %s' % (cmd_data.name, e))
 
 
 def Main(argv):