Work around wxWidgets failure to send first key through validator.
Unify treatment of INDETERMINATE values (such as for multiple
selections with mixed values).
(cherry picked from commit 7308729)
The general idea is to support user-units inheritance. The
UNIT_BINDER allows wrapped controls to inherit units from their
parent dialog, while KEYWAY_HOLDER and DIALOG_SHIM allow child
KEYWAY_HOLDERs or DIALOG_SHIMs to inherit units from their
parent.
The GetUserUnits() method signature has to move to KEYWAY_HOLDER
rather than KEYWAY_PLAYER (where it makes more sense) as it’s the
only common ancestor of KEYWAY_PLAYER and DIALOG_SHIM.
As long as we'll be using the UNIT_BINDER more widely, it also
makes sense to move evaluation and validation into it.
This commit also provides eeschema’s DIALOG_LABEL_EDITOR and
pcbnew’s DIALOG_TRACK_VIA_PROPERTIES and DIALOG_SET_GRID as
models of how to use the new user-units inheritance, eval, and
validation.
Fixes: lp:593795
* https://bugs.launchpad.net/kicad/+bug/593795
(cherry picked from commit c8bc53e)
Jeff Young
Maciej Suminski