vim-patch:8.2.0186: a couple of tests may fail when features are missing

Problem:    A couple of tests may fail when features are missing.
Solution:   Check for features. (Dominique Pelle, closes vim/vim#5561)

705724e430

Just copy the two 'wincolor' test functions from Vim.

Co-authored-by: Bram Moolenaar <Bram@vim.org>

test/old/testdir/test_highlight.vim

@@ -593,6 +593,57 @@ func Test_cursorline_with_visualmode()
   call delete('Xtest_cursorline_with_visualmode')
 endfunc
 
+func Test_wincolor()
+  CheckScreendump
+
+  let lines =<< trim END
+	set cursorline cursorcolumn rnu
+	call setline(1, ["","1111111111","22222222222","3 here 3","","the cat is out of the bag"])
+	set wincolor=Pmenu
+	hi CatLine guifg=green ctermfg=green
+	hi Reverse gui=reverse cterm=reverse
+	syn match CatLine /^the.*/
+	call prop_type_add("foo", {"highlight": "Reverse", "combine": 1})
+	call prop_add(6, 12, {"type": "foo", "end_col": 15})
+	/here
+  END
+  call writefile(lines, 'Xtest_wincolor')
+  let buf = RunVimInTerminal('-S Xtest_wincolor', {'rows': 8})
+  call term_wait(buf)
+  call term_sendkeys(buf, "2G5lvj")
+  call term_wait(buf)
+
+  call VerifyScreenDump(buf, 'Test_wincolor_01', {})
+
+  " clean up
+  call term_sendkeys(buf, "\<Esc>")
+  call StopVimInTerminal(buf)
+  call delete('Xtest_wincolor')
+endfunc
+
+func Test_wincolor_listchars()
+  CheckScreendump
+  CheckFeature conceal
+
+  let lines =<< trim END
+	call setline(1, ["one","\t\tsome random text enough long to show 'extends' and 'precedes' includingnbsps, preceding tabs and trailing spaces    ","three"])
+	set wincolor=Todo
+	set nowrap cole=1 cocu+=n
+	set list lcs=eol:$,tab:>-,space:.,trail:_,extends:>,precedes:<,conceal:*,nbsp:#
+	call matchadd('Conceal', 'text')
+	normal 2G5zl
+  END
+  call writefile(lines, 'Xtest_wincolorlcs')
+  let buf = RunVimInTerminal('-S Xtest_wincolorlcs', {'rows': 8})
+
+  call VerifyScreenDump(buf, 'Test_wincolor_lcs', {})
+
+  " clean up
+  call term_sendkeys(buf, "\<Esc>")
+  call StopVimInTerminal(buf)
+  call delete('Xtest_wincolorlcs')
+endfunc
+
 func Test_cursorcolumn_insert_on_tab()
   CheckScreendump