patch 8.1.1925: more functions can be used as methods

Problem:    More functions can be used as methods.
Solution:   Make various functions usable as a method.
diff --git a/src/testdir/test_edit.vim b/src/testdir/test_edit.vim
index 32569b6..799642d 100644
--- a/src/testdir/test_edit.vim
+++ b/src/testdir/test_edit.vim
@@ -199,11 +199,11 @@
   endfu
   au InsertCharPre <buffer> :call DoIt()
   call feedkeys("A\<f5>\<c-p>u\<cr>\<c-l>\<cr>", 'tx')
-  call assert_equal(["Jan\<c-l>",''], getline(1,'$'))
+  call assert_equal(["Jan\<c-l>",''], 1->getline('$'))
   %d
   call setline(1, 'J')
   call feedkeys("A\<f5>\<c-p>u\<down>\<c-l>\<cr>", 'tx')
-  call assert_equal(["January"], getline(1,'$'))
+  call assert_equal(["January"], 1->getline('$'))
 
   delfu ListMonths
   delfu DoIt
@@ -345,7 +345,7 @@
   call cursor(2, 4)
   call feedkeys("R^\<c-d>", 'tnix')
   call assert_equal(["\tabc", "def"], getline(1, '$'))
-  call assert_equal([0, 2, 2, 0], getpos('.'))
+  call assert_equal([0, 2, 2, 0], '.'->getpos())
   %d
   call setline(1, ["\tabc", "\t\tdef"])
   call cursor(2, 2)