Define default value for all #properties in hook_element_info()

Here is a quick patch that defines defaults to fix the two most common notices for my sites.

todo:

1. Check that really all properties have defaults.
2. Decide what the defaults should be.

This patch makes the following changes:

First I changed the part of the code that transfers the #properties from $element to $element['select'] to only transfer the properties that are present. After that the following #properties were still used (without checking for existence) in select_or_other_element_process(): #default_value, #options, #other_unknown_defaults, #other_delimiter, #multiple, #other, #attributes, #select_type.

This means that #attributes, #options, #other_unknown_defaults and #other_delimiter were missing. This patch defines them as follows:

array(
      '#options' => array(),
      '#other_unknown_defaults' => 'other',
      '#other_delimiter' => '',
      '#attributes' => array(),
)

Additionally processing related to #disabled can be dropped. It is propagated to child-elements automatically by form_builder(). The special case for #other_size is already handled by the loop a few lines above and can be dropped.

Forgot to attach the patch.

I don't see a default setting for #size. Doesn't this cause notices if #size isn't set?

The line with #size is removed in my patch - so no this won't throw notices ;)

Let's follow core's coding standards here and either put all values on the same line, or one value per line.
I would also like to see test coverage for this.

Both true - I'd love to see test coverage too. But it seems that that's the limit of time that I can invest at this point. If you want anything more you'll need to find someone else to do it. BTW: this function seems to be perfectly unit-testable which is rather seldom in the Drupalverse.

Good luck!