Auto merge of #109 - servo:obsolete-mac-dev, r=nox
Auto merge of #109 - servo:obsolete-mac-dev, r=nox

Remove some code that redefined mac_dev_ref_unit_factory incorrectly.



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UK992/saltfs,servo/saltfs,rwaweber/saltfs,rwaweber/saltfs,rwaweber/saltfs,setupminimal/saltfs,UK992/saltfs,UK992/saltfs,ALikhachev/saltfs,setupminimal/saltfs,setupminimal/saltfs,ALikhachev/saltfs,servo/saltfs,ALikhachev/saltfs