html.window.getComputedStyleMap, is not defined

[ghost]

html.window.getComputedStyleMap(html.querySelector('#test'),'');

Gives error:

Uncaught TypeError: window.getComputedStyleMap is not a function
    at Object.main (index.dart:4)

As per MDN docs, html.window.getComputedStyleMap() should be replaced with window.getComputedStyle().

https://developer.mozilla.org/en-US/docs/Web/API/Window/getComputedStyle

At the moment window.getComputedStyle() is not available in dart:html package.

dart sdk version: 2.0.0

Chromium version: Version 70.0.3538.67 (Official Build) Arch Linux (64-bit)

[natebosch]

Here is a potential workaround but I have not tested it extensively...

Iterable<CssStyleRule> findStyles(Element element) sync* {
  for (final sheet in document.styleSheets.whereType<CssStyleSheet>()) {
    if (sheet.disabled) continue;
    if (!window.matchMedia(sheet.media.mediaText).matches) continue;
    for(final rule in sheet.cssRules.whereType<CssStyleRule>()) {
      if (element.matches(rule.selectorText)) yield rule;
    }
  }
}