scopeSubtree doesn't work on SVG elements

[ktiedt]

It appears that there are 2 code paths happening for style scoping... one here: https://github.com/Polymer/polymer/blob/master/src/standard/styling.html#L122 which does not treat SVG consistently due to the possibility that SVG elements can sometimes have .className == an SVGAnimatedString object... this will cause scopeSubtree to "skip" them since className = "new string" will just fail silently.

It seems the fix for #1490 should be expanded to be more generic to encompass all cases where styling my cross path with SVG elements.

Huge thanks to @arthurevans for helping track down why some SVG elements worked and others did not and still some did only under certain conditions.

Tagging @sorvell since the related fixes were primarily his work.

[ktiedt]

Is there by chance a rough ETA on when this might get fixed? Team lead will be asking for details in our next meeting, hoping to have something I can give them. Thanks!

[ktiedt]

Ping? still looking for any feedback here...

[arthurevans]

@sorvell @kevinpschaaf @sjmiles It seems like scopeSubtree should be using Polymer.StyleTransformer rather than going its own way...?

[dfreedm]

Is there a simple test case that I could include for the patch I'm writing?

[ktiedt]

A simple D3 chart inside an element would suffice, that is how I came across this problem. I can see about creating a demo if you aren't able to.

[arthurevans]

retcon'ing bug title so it'll make more sense in the release notes. Because yes, I care.