dart-lang/spark — pull request #1659 by ussuri (2014-04-22 01:57:05+00:00)
Title: Fix spark-menu-button not opening menu on click

TBR @jmesserly: John, any word of wisdom as to why data binding doesn't work here on its own would be appreciated.

The fix that was previously required for the deployed code to work is now required in undeployed code too: the direct assignment of the contained spark-overlay's `opened` attribute; auto-assignment via a data binding doesn't work.