patch 8.2.1252: ":marks" may show '< and '> mixed up

Problem:    ":marks" may show '< and '> mixed up.
Solution:   Show the mark position as where '< and '> would jump.
diff --git a/src/testdir/test_marks.vim b/src/testdir/test_marks.vim
index e4ab562..40242c0 100644
--- a/src/testdir/test_marks.vim
+++ b/src/testdir/test_marks.vim
@@ -105,33 +105,43 @@
   new Xtwo
   call setline(1, ['ccc', 'ddd'])
   norm! $mcGmD
+  exe "norm! GVgg\<Esc>G"
   w!
 
   b Xone
   let a = split(execute('marks'), "\n")
   call assert_equal(9, len(a))
-  call assert_equal('mark line  col file/text', a[0])
-  call assert_equal(" '      2    0 bbb", a[1])
-  call assert_equal(' a      1    0 aaa', a[2])
-  call assert_equal(' B      2    2 bbb', a[3])
-  call assert_equal(' D      2    0 Xtwo', a[4])
-  call assert_equal(' "      1    0 aaa', a[5])
-  call assert_equal(' [      1    0 aaa', a[6])
-  call assert_equal(' ]      2    0 bbb', a[7])
-  call assert_equal(' .      2    0 bbb', a[8])
+  call assert_equal(['mark line  col file/text',
+        \ " '      2    0 bbb",
+        \ ' a      1    0 aaa',
+        \ ' B      2    2 bbb',
+        \ ' D      2    0 Xtwo',
+        \ ' "      1    0 aaa',
+        \ ' [      1    0 aaa',
+        \ ' ]      2    0 bbb',
+        \ ' .      2    0 bbb'], a)
 
   b Xtwo
   let a = split(execute('marks'), "\n")
-  call assert_equal(9, len(a))
-  call assert_equal('mark line  col file/text', a[0])
-  call assert_equal(" '      1    0 ccc", a[1])
-  call assert_equal(' c      1    2 ccc', a[2])
-  call assert_equal(' B      2    2 Xone', a[3])
-  call assert_equal(' D      2    0 ddd', a[4])
-  call assert_equal(' "      2    0 ddd', a[5])
-  call assert_equal(' [      1    0 ccc', a[6])
-  call assert_equal(' ]      2    0 ddd', a[7])
-  call assert_equal(' .      2    0 ddd', a[8])
+  call assert_equal(11, len(a))
+  call assert_equal(['mark line  col file/text',
+        \ " '      1    0 ccc",
+        \ ' c      1    2 ccc',
+        \ ' B      2    2 Xone',
+        \ ' D      2    0 ddd',
+        \ ' "      2    0 ddd',
+        \ ' [      1    0 ccc',
+        \ ' ]      2    0 ddd',
+        \ ' .      2    0 ddd',
+        \ ' <      1    0 ccc',
+        \ ' >      2    0 ddd'], a)
+  norm! Gdd
+  w!
+  let a = split(execute('marks <>'), "\n")
+  call assert_equal(3, len(a))
+  call assert_equal(['mark line  col file/text',
+        \ ' <      1    0 ccc',
+        \ ' >      2    0 -invalid-'], a)
 
   b Xone
   delmarks aB