dijit.form.Select is too tall in high contrast mode under Claro theme

[zhuxw]

When using high contrast mode, the dijit.form.Select widget becomes much taller than usual.

Cause: The "display: block" in claro theme file has overridden the "display: none" fix in dijit.css for a11y issues:

dijit/themes/dijit.css line 163

.dijit_a11y div.dijitArrowButtonInner
...
{
  display: none //This is correct!
}

dijit/themes/claro/form/select.css line 49:

.claro .dijitSelect .dijitArrowButton .dijitArrowButtonInner{
  ...
  display: block //This overrides the previous one!
}

[zhuxw]

dijit.form.Select in high contrast mode

[bill]

Good catch, my tests show that display:block isn't needed at all anyway, so I'll remove it.

[bill]

(In [23234]) Remove unneeded display:block that was making Select too tall in high contrast mode, fixes #11975.