textPath not in the right place when using Ember

I build a small, example Ember application that relates to an issue I am having. In it, I have an SVG drawing with a path and a textPath element on it. Unfortunately, the textPath does not show up, it has 0 height and width in the browser, and is in the wrong position.

Here is an ember-twiddle illustrating the bug. There should be text "Hello World" following the arc. In Chrome 48 this worked fine, but in Chrome 49, it does not. It also does not work in the latest version of Firefox.

Is this a bug with Ember or the browsers? Is there a way to work around this bug?

I filed an issue with Ember, though haven't gotten any response. It is strange that it worked in Chrome 48, but now in 49 it does not. The twiddle doesn't work in Safari for me, but my other testing shows that it works fine in Safari. IE11 also appears to be fine.