[ShadyCSS] Mixins applied inconsistently

[TomK]

REF Polymer/polymer#4115
Distributed nodes appear to be styled with mixins defined in the host, providing they are applied after the host has been defined.

Please note the following demo: http://codepen.io/oridan/pen/edqMPO?editors=1000
Item B simply extends Item A with no other changes. Therefore they should both display exactly the same. The expected result as I understand it should be per as the following image:

RFC:
I have resolved this where nativeCssVariables == true by applying the following two diffs:
webcomponents/shadycss@master...TomK:apply-host-descendants - quite inefficient
webcomponents/shadycss@master...TomK:refresh-invalid-shim

I understand this is not a complete resolution, and possibly this implementation is not feasible. So I am hoping for comments/suggestions to steer towards a viable solution.

[dfreedm]

Thanks for the test case. I think I have a simpler method that moves the invalid flag onto the element instances.
Then sometime later, you can trigger an applyStyle on all of them.

[TomK]

@azakus any updates on this issue please?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.