Disabled Tabs are enabled on small screens

[Blackbaud-ScottFreeman]

Expected behavior

You should not be able to select a disabled tab no matter how the tabs are displayed.

Actual behavior

When the screen size is small enough to require tabs to be placed in a drop down, disabled tabs are able to be selected

Steps to reproduce

1. Go to the plunker sample below.
2. Shrink the preview screen until the tabs are placed in a drop down.
3. Notice that you can select the Disabled tab.

Plunker

https://plnkr.co/edit/XH6aXA16tPW4lBfb1dXh?p=preview

[Blackbaud-PatrickOFriel]

In 2.0.0-beta.24