We have a situation where some clients drop their old offer before
creating a new one. This means klipper tries to fill in the empty
clipboard at the same time the client posts its new real contents.
This adds in a flag (via a hidden mimetype) that klipper is trying to
replace a null clipboard. If this flag is set and our clipboard is not
null because the client has updated it in the meantime we ignore the
klipper update.
It's a workaround, rather than an ideal fix at a data level, but it
solves the problem in the interim.
CCBUG: 424855
Summary:
This patch makes use of wlroot's DataControl interface to support
clipboard management.
Unlike wl_data_device clipboards are sent on every change to all
watchers.
If the data device has a selection set it updates immediately.
Because it was started a year ago it uses the existing style of
wrapping objects. The unit test uses the new approach.
Test Plan:
Updated kwin
used wlroot's wl-copy, wl-paste which are xclip replacements to
show that the clipboard updated correctly
Reviewers: #kwin
Differential Revision: https://phabricator.kde.org/D29330
