commit 4f036439 "Kill unused
TBX_UPDATER_MODE_NONE." removed TBX_UPDATER_MODE_NONE, but it was
actually used, but written as literal 0 in ctor (default value for
nMode). Worse, TBX_UPDATER_MODE_NONE meant "draw a square color mark"
(!) and after removing it color-marks were not drawn for some buttons,
e.g. frame color button.

This patch makes use of TBX_UPDATER_MODE_CHAR_COLOR_NEW (which means
"draw a rectangle color mark") everywhere, TBX_UPDATER_MODE_CHAR_COLOR
and TBX_UPDATER_MODE_CHAR_BACKGROUND were unused.

Change-Id: I7452bf73227cd7038e5ea9ab740745125ca079b4