[FIX] web: fix mock server dropping x2many on update

Previously, when an update operation was performed, the list of
ids in the x2many field was emptied beforehand.

It kinda worked in lots of cases where one would expect it to
fail because in thoses cases the widgets send link_to commands
along with the update one, thus re-adding the removed line.

Now the behavior is more consistent accross the board. We start
with the current list of ids and apply the requested changes.

0 files changed, 0 insertions, 0 deletions