bug#14738: 24.3.50; defcustom :type (repeat (codrew.adams@oracle.comns symbol plist)) when nil is the default value.

[Katsumi Yamaoka]

Drew Adams wrote:
>>> This is what I see, with nil as the default value of the option:
>>>
>>> ,----
>>>| Hide Gnus Face Properties Alist:
>>>| INS
>>>|     State : STANDARD.
>>>|    Alist....
>>>| Groups: Gnus Article Headers
>>> `----
>>
>> What if you try to INS now?  Does the plist have INS buttons?

> No, I see the same problem.

Maybe I am the culprit.  This seems to be a side effect of:

2013-01-07  Katsumi Yamaoka  <yamaoka@jpl.org>

        * wid-edit.el (widget-default-get): Work for inlined elements.
        (Bug#12670)

cf. http://news.gmane.org/group/gmane.emacs.bugs/thread=65693

> Plus, with the non-nil default value, the two INS buttons in the
> Plist field act the same (there should not be two, one paired
> with DEL and one alone).

I'm going to fix it, but

> Plus, all but the first INS DEL pair are indented differently
> from the first pair.

this seems to be due to another cause since reverting my patch
doesn't help.