Matan Ziv-Av authored Apr 12, 2022 and Kurt Hindenburg committed Apr 19, 2022

Moving all cursor and scroll handling to addPlacement.

This requires the moveCursor parameter to have three possible values,
since Sixel cursor movement is not the same as Kitty/iterm2. This also
unnecessitates addPlacement return value.

BUG: 452476
(cherry picked from commit 9ae57f4e)