Docking into the top bar meant either living inside the Run button's card
and being dragged around with it, or snapping to a row whose geometry we
have to infer from the frontend's markup. Neither is worth the coupling
for a toolbar the user repositions often, so the toolbar now simply stays
wherever it is dropped.
Removes the band probing, the dock guide, the Run card avoidance and the
resize tracking that existed only to keep a docked toolbar aligned.
kk8bit
affc001629