patch 8.2.2842: Vim9: skip argument to searchpair() is not compiled

Problem:    Vim9: skip argument to searchpair() is not compiled.
Solution:   Add VAR_INSTR.
diff --git a/src/testdir/test_vim9_builtin.vim b/src/testdir/test_vim9_builtin.vim
index 46fe3e5..3232d9b 100644
--- a/src/testdir/test_vim9_builtin.vim
+++ b/src/testdir/test_vim9_builtin.vim
@@ -974,6 +974,20 @@
   bwipe!
 enddef
 
+def Test_searchpair()
+  new
+  setline(1, "here { and } there")
+  normal f{
+  var col = 15
+  assert_equal(1, searchpair('{', '', '}', '', 'col(".") > col'))
+  assert_equal(12, col('.'))
+  col = 8
+  normal 0f{
+  assert_equal(0, searchpair('{', '', '}', '', 'col(".") > col'))
+  assert_equal(6, col('.'))
+  bwipe!
+enddef
+
 def Test_set_get_bufline()
   # similar to Test_setbufline_getbufline()
   var lines =<< trim END
diff --git a/src/testdir/test_vim9_disassemble.vim b/src/testdir/test_vim9_disassemble.vim
index e7314e4..c4482a5 100644
--- a/src/testdir/test_vim9_disassemble.vim
+++ b/src/testdir/test_vim9_disassemble.vim
@@ -140,6 +140,35 @@
         res)
 enddef
 
+
+def s:SearchPair()
+  var col = 8
+  searchpair("{", "", "}", "", "col('.') > col")
+enddef
+
+def Test_disassemble_seachpair()
+  var res = execute('disass s:SearchPair')
+  assert_match('<SNR>\d*_SearchPair.*' ..
+        ' var col = 8\_s*' ..
+        '\d STORE 8 in $0\_s*' ..
+        ' searchpair("{", "", "}", "", "col(''.'') > col")\_s*' ..
+        '\d PUSHS "{"\_s*' ..
+        '\d PUSHS ""\_s*' ..
+        '\d PUSHS "}"\_s*' ..
+        '\d PUSHS ""\_s*' ..
+        '\d INSTR\_s*' ..
+        '  0 PUSHS "."\_s*' ..
+        '  1 BCALL col(argc 1)\_s*' ..
+        '  2 LOAD $0\_s*' ..
+        '  3 COMPARENR >\_s*' ..
+        ' -------------\_s*' ..
+        '\d BCALL searchpair(argc 5)\_s*' ..
+        '\d DROP\_s*' ..
+        '\d RETURN 0',
+        res)
+enddef
+
+
 def s:RedirVar()
   var result: string
   redir =>> result