patch 8.1.1079: no need for a separate ScreenLinesUtf8() test function

Problem:    No need for a separate ScreenLinesUtf8() test function.
Solution:   Get the composing characters with ScreenLines().

src/testdir/test_listchars.vim

@@ -130,7 +130,7 @@ func Test_listchars_composing()
         \ ]
   redraw!
   call cursor(1, 1)
-  let got = ScreenLinesUtf8(1, virtcol('$'))
+  let got = ScreenLines(1, virtcol('$'))
   bw!
   call assert_equal(expected, got)
   let &encoding=oldencoding

src/testdir/test_utf8.vim

@@ -91,7 +91,7 @@ func Test_screenchar_utf8()
   call assert_equal("", screenstring(1, 4))
   call assert_equal("\u3046\u3099", screenstring(1, 5))
 
-  call assert_equal([text . '  '], ScreenLinesUtf8(1, 8))
+  call assert_equal([text . '  '], ScreenLines(1, 8))
 
   bwipe!
 endfunc

src/testdir/view_util.vim

@@ -5,29 +5,10 @@ if exists('*ScreenLines')
   finish
 endif
 
-" Get text on the screen, without composing characters.
-" ScreenLines(lnum, width) or
-" ScreenLines([start, end], width)
-function! ScreenLines(lnum, width) abort
-  redraw!
-  if type(a:lnum) == v:t_list
-    let start = a:lnum[0]
-    let end = a:lnum[1]
-  else
-    let start = a:lnum
-    let end = a:lnum
-  endif
-  let lines = []
-  for l in range(start, end)
-    let lines += [join(map(range(1, a:width), 'nr2char(screenchar(l, v:val))'), '')]
-  endfor
-  return lines
-endfunction
-
 " Get text on the screen, including composing characters.
 " ScreenLines(lnum, width) or
 " ScreenLines([start, end], width)
-function! ScreenLinesUtf8(lnum, width) abort
+function! ScreenLines(lnum, width) abort
   redraw!
   if type(a:lnum) == v:t_list
     let start = a:lnum[0]

src/version.c

@@ -775,6 +775,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1079,
 /**/
     1078,
 /**/