py3: use system strings for HTTP response header comparison
res.headers is holding system strings. Attempting to compare against
bytes always fails and we fail to print decoded CBOR responses on
Python 3.
After this change, various test-wireproto* tests are now properly
printing CBOR response objects.
Differential Revision: https://phab.mercurial-scm.org/D4835
{
// Enforcing
"eqeqeq" : true, // true: Require triple equals (===) for comparison
"forin" : true, // true: Require filtering for..in loops with obj.hasOwnProperty()
"freeze" : true, // true: prohibits overwriting prototypes of native objects such as Array, Date etc.
"nonbsp" : true, // true: Prohibit "non-breaking whitespace" characters.
"undef" : true, // true: Require all non-global variables to be declared (prevents global leaks)
// Environments
"browser" : true // Web Browser (window, document, etc)
}