D15421: [server] Add surface data proxy mechanism

[Roman Gilg]

romangg added a dependency: D15023: [server] Add selectionChanged signal.

REPOSITORY
  R127 KWayland

REVISION DETAIL
  https://phabricator.kde.org/D15421

To: romangg, #kwin
Cc: kde-frameworks-devel, michaelh, ngraham, bruns