Make RefUpdateContext and ScColumn::UpdateReferenceOnCopy() use the same
sc::ColumnBlockPositionSet that CopyFromClipContext uses. Without it
pathological cases like in tdf#112000 trigger quadratic cost because
of repeated mdds searches from the start.
Includes also an mdds patch that allows it to search backwards
from a position hint. Without it, this would be very difficult to fix
otherwise, as CopyFromClip() in ScDocument::CopyBlockFromClip()
moves the position hint past the area that UpdateReferenceOnCopy()
would use. It also just plain makes sense to try to go backwards
in an std::vector.

Change-Id: I985e3a40e4abf1a824e55c76d82579882fa75cc2
Reviewed-on: https://gerrit.libreoffice.org/72424
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>