Pikaday close event confuses ember basic dropdown

I'm not sure if this belongs here, as this is more a conflict with another addon than a pikaday specific problem.
If a pikaday component is inside the content of an `ember-basic-dropdown` component, the dropdown closes as soon as a date is clicked. It seems that the close event for the pikaday calendar is bubbling up tothe dropdown.

```
{{#basic-dropdown renderInPlace=true as | dd | }}
{{#dd.trigger class=triggerClasses eventType="click" }}
Show date picker
{{/dd.trigger}}
{{#dd.content }}
{{pikaday-input format="MM/DD/YYYY" onSelection=(action 'doSomethingOnSelection') onClose=(action 'doSomethingOnClose') bubbles=false}}
{{/dd.content}}
{{/basic-dropdown}}
```

I have tried it with a more simple popout and it works correctly:

```

{{#if foo}}
{{pikaday-input format="MM/DD/YYYY" onSelection=(action 'test') onClose=(action 'doSomethingOnClose') bubbling=false}}
{{/if}}
```
Is there a way to stop the close event of pikaday from bubbling up in such a case?

Start by reproducing the supplied ember-basic-dropdown example with a pikaday-input and compare it with the simpler popout example. Trace the close event when a date is clicked; done means selecting a date no longer closes the dropdown while the standalone picker behavior remains correct.

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