Defaulting a comboBox's buttonCell to the cellFactory

[Urs Reupke]

Hi all,
back in April, Jonathan proposed a change to comboBoxes that allowed
to separate the button's rendering from the list's rendering.[1]

In the JIRA issue accompanying that discussion [2], he also mentioned
ways to render the button when the new buttonCell property is not set:
"If this is not set, there are two options:
1) Use a cell from the ComboBox.cellFactory
2) Not style the button at all, and use a default cell from the skin"

Now, in FX2.2b10, the buttonCell is rendered as toString if the
property is not set.
I believe that his option 1) would be a great improvement to the
behaviour, and Jonathan asked me to make that proposal public.
My reasoning is that those who need the buttonCell to be rendered
differently can do it, whereas those whose buttons and listcells look
alike don't need to think about it. From my experience, the latter
should be the majority.

I appreciate your feedback on the matter.

Thank you
-Urs

[1] http://mail.openjdk.java.net/pipermail/openjfx-dev/2012-April/001209.html
[2] http://javafx-jira.kenai.com/browse/RT-21023