Remove test default value for the other field.

This reverts commit a2809554.

Squashed commit of the following:

commit 9ebf27714844775a771315f7795082605b746ec4
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Tue Dec 15 23:33:05 2015 +0100

    Fix and extend unittests.

commit 06ab2b51f057a37b834865cc8cfd7337c4aa781e
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Tue Dec 15 23:03:07 2015 +0100

    Add hack to also support multiselect elements.

commit 3292bdcf2c85d3007a65c0fce76442588d8c4764
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Tue Dec 15 17:45:47 2015 +0100

    Add states for buttons widget

commit 01ccea1ec9654999c4b7209059a0ff49ad276247
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Tue Dec 15 17:02:01 2015 +0100

    Add states for select widget

commit c35190ff943e97d6780dddc2a27bc0b4f32ac3d7
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Tue Dec 15 16:42:04 2015 +0100

    Implement JS as a library.

Currently 100% coverage of src/Element and ~20% coverage of src/Plugin.

Widgets implementing SelectOrOtherWidgetBase have a high probability of having unique way to determine their available options. SelectOrOtherWidgetBase should therefor not be opinionated.

By doing so we can remove the custom constructor.

This reverts commit 9e1577da.

commit 26c45bdc5e84bcc7c1b0852a3dc8cc7c844acae4
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 22:58:51 2015 +0100

    Add initial unittests.

commit 7f479efd9c9f9dcd1232db3d583f576b1f7337b3
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 21:49:56 2015 +0100

    Add other option to options.

commit 419724763d17c36814ab0c04c583f7e50b19dd3d
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 21:18:08 2015 +0100

    Fix type selection

commit a5adc56c1b630484cae45a2ba199ea8416b84201
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 21:12:19 2015 +0100

    Make select element type configurable.

commit 64ad6b0e73a707ac9e6ecc3861dbed73d7f97dcc
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 20:56:36 2015 +0100

    Refactor element class into base class and subclasses

commit 2bca991ddc7ae38e322c1edc544187df9d137d8f
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 20:42:54 2015 +0100

    Remove obsolete calidate callback

commit 6ea71eb4c4c5eac278f17e296d7feef7db8bfc37
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 20:39:46 2015 +0100

    Properly implement value callback

commit 59a42ac0dff4aab285d12d883ea4df5da4183c80
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 20:28:25 2015 +0100

    Get basic select and other elements rendered

commit 83eae18a63537205d4278cfcaf9b060ddd9580d2
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 20:09:39 2015 +0100

    Get some logic into valueCallback

commit df7b292010dee6f504855255ff985f56da1afa2b
Author: legolasbo <legolasbo@2480548.no-reply.drupal.org>
Date:   Fri Dec 11 20:06:27 2015 +0100

    Get basic element scaffolding going

Select (or other) widget.

element.

of select list.

hidden.

hidden.

label translations from widget.