[ally.is.focusRelevant] missing test: <area> without href attribute

[rodneyrehm]

Concerning: ally.is.focusRelevant
User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:42.0) Gecko/20100101 Firefox/42.0
ally.js version: 1.0.1

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Steps to reproduce the problem

add <area shape="rect" coords="63,19,144,45" data-label="area[href].upper"> (href attribute missing on purpose) to focusable/test.html and re-run test.

Firefox considers that element tabbable, Chrome inert. see bin