patch 8.1.1400: using global pointer for tab-local popups is clumsy

Problem:    Using global pointer for tab-local popups is clumsy.
Solution:   Use the pointer in tabpage_T.
diff --git a/src/version.c b/src/version.c
index 78a932e..4f87663 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1400,
+/**/
     1399,
 /**/
     1398,