vim-patch:8.2.{2518,2520,3572,3588}: 'listchars' (and 'fillchars'?) fixes

vim-patch:8.2.3627: difficult to know where the text starts in a window

Problem:    difficult to know where the text starts in a window. (Sergey
            Vlasov)
Solution:   Add the "textoff" entry in the result of getwininfo().
            (closes vim/vim#9163)
https://github.com/vim/vim/commit/cdf5fdb2948ecdd24c6a1e27ed33dfa847c2b3e4

Fix indent in Test_getbufwintabinfo().

vim-patch:8.2.{3468,3617,3618,3622}: some other CWD related patches

Problem:    ci" finds following string but ci< and others don't.
Solution:   When not inside an object find the start. (Connor Lane Smit,
            closes vim/vim#8670)
https://github.com/vim/vim/commit/b9115da4bec5e6cfff69da85cc47c42dd67e42e4

Problem:    On a narrow screen ":hi" output is confusing.
Solution:   Insert a space between highlight group name and "xxx". (Masato
            Nishihaga, closes vim/vim#4599)
https://github.com/vim/vim/commit/548be7f126dc57ca861cb26dc6492c3b2a9e2c99

Problem:    getcompletion() always passes zero as position to custom
            completion function.
Solution:   Pass the pattern length. (closes vim/vim#9173)
https://github.com/vim/vim/commit/4785fe02bba14c4e0aede0fa425ca790a1cb98d7

Co-authored-by: ii14 <ii14@users.noreply.github.com>

Problem:    "verbose pwd" shows confusing info when :lcd does not change
            directory.
Solution:   Clear last_chdir_reason also when the directory does not change.
            (closes vim/vim#9160)
https://github.com/vim/vim/commit/64be6aa3a54ecfe355d4a03e1200650c301e7f29

This only ports the tests, as this is already Nvim's behavior.

Problem:    getcwd() is unclear about how 'autochdir' is used.
Solution:   Update the help for getcwd().  Without any arguments always return
            the actual current directory. (closes vim/vim#9142)
https://github.com/vim/vim/commit/851c7a699ae00bdc14a4db874cf722b7b7393b53

Problem:    ":verbose pwd" does not mention 'autochdir' was applied.
Solution:   Remember the last chdir was done by 'autochdir'.  (issue vim/vim#9142)
https://github.com/vim/vim/commit/0526815c15170a5926e1008600ec29d42d8b64c2

Problem:    Problem with :cd when editing file in non-existent directory. (Yee
            Cheng Chin)
Solution:   Prepend the current directory to get the full path. (closes vim/vim#8903)
https://github.com/vim/vim/commit/c6376c798433bcb9ee38a8664299d11454546950