[issue15376] Refactor the test_runpy walk_package support code into a common location

[Nick Coghlan]

Nick Coghlan added the comment:

test.support is now a subpackage in both 3.3 and default, but test.support.package_helper still needs to be created (see comments on #15403)

----------
versions: +Python 3.4

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue15376>
_______________________________________