{{#paper-menu-content-pane width=width}}
  {{yield this}}
{{/paper-menu-content-pane}}
{{#ember-wormhole to="paper-wormhole"}}
  {{paper-backdrop  tap="toggleMenu"}}
{{/ember-wormhole}}
{{#paper-menu-content-pane width=width}}
  {{yield this}}
{{/paper-menu-content-pane}}
{{#ember-wormhole to="paper-wormhole"}}
  {{paper-backdrop class="md-menu-backdrop" tap="toggleMenu"}}
{{/ember-wormhole}}

Add class to menu backdrop
Add class to menu backdrop

Fixes #254

This allows targeting this backdrop for z-index, so that clicks work properly.