vim: Import v8.1.2168

* 8.1.2168: heredoc assignment not skipped in if block
* 8.1.2167: mapping test fails on MS-Windows
* 8.1.2166: rubyeval() not tested as a method
* Update runtime files.
* 8.1.2165: mapping test fails on Mac
* 8.1.2164: stuck when using "j" in a popupwin with popup_filter_menu
* 8.1.2163: cannot build with +spell but without +syntax
* 8.1.2162: popup resize test is flaky
* 8.1.2161: mapping test fails
* 8.1.2160: cannot build with +syntax but without +terminal
* 8.1.2159: some mappings are listed twice
* 8.1.2158: terminal attributes missing in Terminal-normal mode
* 8.1.2157: libvterm source files missing from distribution
* 8.1.2156: first character after Tab is not highlighted
* 8.1.2155: in a terminal window 'cursorlineopt' does not work properly
* 8.1.2154: quickfix window height wrong when there is a tabline
* 8.1.2153: combining text property and syntax highlight is wrong

Author: chrisbra

gitlog.txt

@@ -1 +1 @@
-* [8.1.2152](https://github.com/vim/vim/releases/tag/v8.1.2152): problems navigating tags file on MacOS Catalina
+* [8.1.2168](https://github.com/vim/vim/releases/tag/v8.1.2168): heredoc assignment not skipped in if block\n* [8.1.2167](https://github.com/vim/vim/releases/tag/v8.1.2167): mapping test fails on MS-Windows\n* [8.1.2166](https://github.com/vim/vim/releases/tag/v8.1.2166): rubyeval() not tested as a method\n* Update runtime files.\n* [8.1.2165](https://github.com/vim/vim/releases/tag/v8.1.2165): mapping test fails on Mac\n* [8.1.2164](https://github.com/vim/vim/releases/tag/v8.1.2164): stuck when using "j" in a popupwin with popup_filter_menu\n* [8.1.2163](https://github.com/vim/vim/releases/tag/v8.1.2163): cannot build with +spell but without +syntax\n* [8.1.2162](https://github.com/vim/vim/releases/tag/v8.1.2162): popup resize test is flaky\n* [8.1.2161](https://github.com/vim/vim/releases/tag/v8.1.2161): mapping test fails\n* [8.1.2160](https://github.com/vim/vim/releases/tag/v8.1.2160): cannot build with +syntax but without +terminal\n* [8.1.2159](https://github.com/vim/vim/releases/tag/v8.1.2159): some mappings are listed twice\n* [8.1.2158](https://github.com/vim/vim/releases/tag/v8.1.2158): terminal attributes missing in Terminal-normal mode\n* [8.1.2157](https://github.com/vim/vim/releases/tag/v8.1.2157): libvterm source files missing from distribution\n* [8.1.2156](https://github.com/vim/vim/releases/tag/v8.1.2156): first character after Tab is not highlighted\n* [8.1.2155](https://github.com/vim/vim/releases/tag/v8.1.2155): in a terminal window 'cursorlineopt' does not work properly\n* [8.1.2154](https://github.com/vim/vim/releases/tag/v8.1.2154): quickfix window height wrong when there is a tabline\n* [8.1.2153](https://github.com/vim/vim/releases/tag/v8.1.2153): combining text property and syntax highlight is wrong