[webcomponents] Resize events needed? (#352)

Sorry I'm out of the loop but this issue came up before and I have no idea if it has been addressed

Assume you want to make a custom graphing element `<graph>`. To do this you use a canvas element wrapped in whatever is needed to make it a custom element. Anytime the element changes size the element's code needs to re-render the graph to fit the new size of the element.

As far as I am aware this is currently impossible. The only resize element is on `window` and there are plenty of other reasons an element might change size from css animations or other settings to flexboxes. A good example is Chrome's or Firefox's dev tools. Both of them have areas whose sizes can be changed without changing the size of the window. 

![graph](https://cloud.githubusercontent.com/assets/234804/11430556/cc98a3dc-94cb-11e5-8847-7f947b364c63.gif)

For example if the graph on the right was a custom element it would have no way to know it had been resized. It's only options are (1) require the user to notify it or (2) poll its size.

Has this been addressed? One solution would be an element level resize event. Maybe there are others.


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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/352