vim: Import v8.1.1446

* 8.1.1446: popup window callback not implemented yet
* 8.1.1445: popup window border highlight not implemented yet
* 8.1.1444: not using double line characters for popup border
* 8.1.1443: popup window padding and border not implemented yet
* 8.1.1442: popup windows not considered when the Vim window is resized
* 8.1.1441: popup window filter not yet implemented
* 8.1.1440: win_execute() test fails
* 8.1.1439: json_encode() is very slow for large results
* 8.1.1438: some commands cause trouble in a popup window
* 8.1.1437: code to handle callbacks is duplicated

Author: chrisbra

gitlog.txt

@@ -1 +1 @@
-* Update runtime files.\n* [8.1.1436](https://github.com/vim/vim/releases/tag/v8.1.1436): writefile test fails when run under /tmp\n* [8.1.1435](https://github.com/vim/vim/releases/tag/v8.1.1435): memory usage test is a bit too flaky\n* [8.1.1434](https://github.com/vim/vim/releases/tag/v8.1.1434): test 3 is old style\n* [8.1.1433](https://github.com/vim/vim/releases/tag/v8.1.1433): win_execute() may leave popup window focused
+* [8.1.1446](https://github.com/vim/vim/releases/tag/v8.1.1446): popup window callback not implemented yet\n* [8.1.1445](https://github.com/vim/vim/releases/tag/v8.1.1445): popup window border highlight not implemented yet\n* [8.1.1444](https://github.com/vim/vim/releases/tag/v8.1.1444): not using double line characters for popup border\n* [8.1.1443](https://github.com/vim/vim/releases/tag/v8.1.1443): popup window padding and border not implemented yet\n* [8.1.1442](https://github.com/vim/vim/releases/tag/v8.1.1442): popup windows not considered when the Vim window is resized\n* [8.1.1441](https://github.com/vim/vim/releases/tag/v8.1.1441): popup window filter not yet implemented\n* [8.1.1440](https://github.com/vim/vim/releases/tag/v8.1.1440): win_execute() test fails\n* [8.1.1439](https://github.com/vim/vim/releases/tag/v8.1.1439): json_encode() is very slow for large results\n* [8.1.1438](https://github.com/vim/vim/releases/tag/v8.1.1438): some commands cause trouble in a popup window\n* [8.1.1437](https://github.com/vim/vim/releases/tag/v8.1.1437): code to handle callbacks is duplicated