patch 9.0.2015: Vim9: does not handle islocked() from a method correctly Commit: https://github.com/vim/vim/commit/4c8da025ef8140168b7a09d9fe922ce4bb40f19d Author: Ernie Rael <errael@raelity.com> Date: Wed Oct 11 21:35:11 2023 +0200 patch 9.0.2015: Vim9: does not handle islocked() from a method correctly Problem: Vim9: does not handle islocked() from a method correctly Solution: Handle islocked() builtin from a method. - Setup `lval_root` from `f_islocked()`. - Add function `fill_exec_lval_root()` to get info about executing method. - `sync_root` added in get_lval to handle method member access. - Conservative approach to reference counting. closes: #13309 Signed-off-by: Christian Brabandt <cb@256bit.org> Co-authored-by: Ernie Rael <errael@raelity.com>