vim-patch:8.2.1783: try-catch test fails

Problem:    Try-catch test fails.
Solution:   Don't call win_enter(), only call enterering_window().
bdf931c25b

v8.2.1781 caused Test_reload_in_try_catch() from v8.2.0004 to fail in Vim, but
it has not been ported yet.

src/nvim/autocmd.c

@@ -1208,15 +1208,18 @@ win_found:
 
     win_T *const save_curwin = win_find_by_handle(aco->save_curwin_handle);
     if (save_curwin != NULL) {
-      win_enter(save_curwin, true);
+      curwin = save_curwin;
     } else {
       // Hmm, original window disappeared.  Just use the first one.
       curwin = firstwin;
     }
+    curbuf = curwin->w_buffer;
+    // May need to restore insert mode for a prompt buffer.
+    entering_window(curwin);
+
     prevwin = win_find_by_handle(aco->save_prevwin_handle);
     vars_clear(&aucmd_win->w_vars->dv_hashtab);         // free all w: variables
     hash_init(&aucmd_win->w_vars->dv_hashtab);          // re-use the hashtab
-    curbuf = curwin->w_buffer;
 
     xfree(globaldir);
     globaldir = aco->globaldir;

src/nvim/testdir/runtest.vim

@@ -197,7 +197,12 @@ func RunTheTest(test)
 
   " Close any extra tab pages and windows and make the current one not modified.
   while tabpagenr('$') > 1
+    let winid = win_getid()
     quit!
+    if winid == win_getid()
+      echoerr 'Could not quit window'
+      break
+    endif
   endwhile
 
   while 1

src/nvim/window.c

@@ -2256,7 +2256,7 @@ static void leaving_window(win_T *const win)
   }
 }
 
-static void entering_window(win_T *const win)
+void entering_window(win_T *const win)
   FUNC_ATTR_NONNULL_ALL
 {
   // Only matters for a prompt window.