Set State_KeyboardFocusChange if focus has been requested by keyboard

Some styles (QFusionStyle, QGtkStyle) don't draw a focus rectangle if
QStyle::State_KeyboardFocusChange is not set. This patch is based on
change,84388 in QtDeclarative.

Change-Id: Ic0c0bdd68689055cff12d601e64b77b53e7980dd
Reviewed-by: Liang Qi <liang.qi@digia.com>
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>