Attribute bindings change in 0.2.7

{{bind-attr class=" test-class " }} results in class=" " after upgrade from 0.2.5 to 0.2.7

bind-attrs helper lost raison d’etre when HTMLBars introduced new attribute binding syntax in Ember 1.10:

// why do this...
<element {{bind-attrs class=":item item.isActive:active:disabled" title=item.title}}>

// when you can do this?
<element class="item {{if item.isActive "active" "disabled"}}" title="{{item.title}}">