<style> example breaks editor

[wbamberg]

The example for <style> breaks the editor UI when the CSS is edited:

I have no idea why. It's possible that <style> won't be suitable for an interactive example.

[stephanmax]

I think what blows up here is this code inside the render function in editor.js:

var styleElements = shadow.querySelectorAll('style'); // A

for (var styleElement in styleElements) {
    if (styleElements.hasOwnProperty(styleElement)) {
        shadow.removeChild(styleElements[styleElement]); // B
    }
}

All style elements are selected (A), including the one coming from inside the HTML editor. Since that one is not a direct child of the shadow root, calling removeChild (B) on it throws an error. The render method exits and we are left with only the div element but no more style elements.

I think deleting the div first (and the style element from the HTML editor with it), before we query the DOM, is the cheapest solution here. PR is coming right up.