On OSX with Editable combo box the button is not aligned correctly with the combobox field

[Paul Taylor]

With Editable combo box the button is not aligned correctly with the 
combobox field, at least I don't think so I'm struggling to find an 
example of editable combo in a native OSX application.
Its worse using size variant small, with non editable combobox its fine.

Same problem on Java 7 and Java 8

This screenshot shows three cases
http://www.jthink.net/jaikoz/images/combos%20not%20aligned.jpg

Language, editable small (JComponent.sizeVariant)
Script, no editable small
Genre, editable normal