patch 9.1.1461: tabpanel: tabpanel vanishes with popup menu

Problem:  tabpanel: tabpanel vanishes with popup menu
Solution: remove pum-related test in tabpanel_leftcol(), refactor a few
          related functions (Hirohito Higashi)

This commit does the following:
- Delete unnecessary pum-related checks in the tabpanel_leftcol()
  function
- remove pum-related check in tabpanel_leftcol()
- The argument of the TPL_LCOL() macro has been deleted.
- The argument of the tabpanel_leftcol() function has been changed
  to void
- The return type of the `win_comp_pos()` function has been changed to
  void

closes: #17549

Signed-off-by: Hirohito Higashi <h.east.727@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_tabpanel.vim b/src/testdir/test_tabpanel.vim
index 0d79650..1790fee 100644
--- a/src/testdir/test_tabpanel.vim
+++ b/src/testdir/test_tabpanel.vim
@@ -693,4 +693,31 @@
 
   call StopVimInTerminal(buf)
 endfunc
+
+function Test_tabpanel_with_cmdline_pum()
+  CheckScreendump
+
+  let lines =<< trim END
+    set showtabpanel=2
+    set noruler
+    tabnew aaa
+    set wildoptions+=pum
+    func TimerCb(timer)
+      tabnew bbb
+    endfunc
+    call timer_start(100, 'TimerCb')
+  END
+  call writefile(lines, 'XTest_tabpanel_with_cmdline_pum', 'D')
+
+  let buf = RunVimInTerminal('-S XTest_tabpanel_with_cmdline_pum', {'rows': 10, 'cols': 45})
+  call term_sendkeys(buf, "\<C-L>")
+  call VerifyScreenDump(buf, 'Test_tabpanel_with_cmdline_pum_0', {})
+  call term_sendkeys(buf, ":set\<Tab>")
+  call term_wait(buf, 120)
+  call VerifyScreenDump(buf, 'Test_tabpanel_with_cmdline_pum_1', {})
+  call term_sendkeys(buf, "\<Esc>:tabclose\<CR>\<C-L>")
+  call VerifyScreenDump(buf, 'Test_tabpanel_with_cmdline_pum_0', {})
+
+  call StopVimInTerminal(buf)
+endfunc
 " vim: shiftwidth=2 sts=2 expandtab