patch 9.0.0950: the pattern "\_s\zs" matches at EOL

Problem:    The pattern "\_s\zs" matches at EOL.
Solution:   Make the pattern "\_s\zs" match at the start of the next line.
            (closes #11617)
diff --git a/src/testdir/test_search.vim b/src/testdir/test_search.vim
index 3576673..e51803d 100644
--- a/src/testdir/test_search.vim
+++ b/src/testdir/test_search.vim
@@ -1884,7 +1884,7 @@
 
   set ignorecase& smartcase&
   let &encoding = save_enc
-  close!
+  bwipe!
 endfunc
 
 " Test searching past the end of a file
@@ -1893,7 +1893,29 @@
   call setline(1, ['Line'])
   exe "normal /\\n\\zs\<CR>"
   call assert_equal([1, 4], [line('.'), col('.')])
-  close!
+  bwipe!
+endfunc
+
+" Test setting the start of the match and still finding a next match in the
+" same line.
+func Test_search_set_start_same_line()
+  new
+  set cpo-=c
+
+  call setline(1, ['1', '2', '3 .', '4', '5'])
+  exe "normal /\\_s\\zs\\S\<CR>"
+  call assert_equal([2, 1], [line('.'), col('.')])
+  exe 'normal n'
+  call assert_equal([3, 1], [line('.'), col('.')])
+  exe 'normal n'
+  call assert_equal([3, 3], [line('.'), col('.')])
+  exe 'normal n'
+  call assert_equal([4, 1], [line('.'), col('.')])
+  exe 'normal n'
+  call assert_equal([5, 1], [line('.'), col('.')])
+
+  set cpo+=c
+  bwipe!
 endfunc
 
 " Test for various search offsets