Problem: Cursor is adjusted in window that did not change in size by
'splitkeep'.
Solution: Only check that cursor position is valid in a window that
has changed in size.
closes: vim/vim#1250916af913eee
Co-authored-by: Luuk van Baal <luukvbaal@gmail.com>
Problem: Cursor not adjusted when near top or bottom of window and
'splitkeep' is not "cursor".
Solution: Move boundary checks to outer cursor move functions, inner
functions should only return valid cursor positions. (Luuk van
Baal, closesvim/vim#12480)
a109f39ef5
