Merge 9.2.6, 9.1.13 and 8.9.19 into their respective branches

I guess this is critical, because anyone tracking the branch won't have the security fixes in 8.9.19.

Merged in 8.9.19, resolved merge conflicts, updated VERSION to 8.9.20-dev.

Actually, it looks like this applies to all branches. None of the security releases have been merged back to 8.9.x, 9.1.x, 9.2.x or 9.3.x:

$ git cherry -v origin/9.2.x 9.2.6
+ 741a4f6bfbfc72202274b56936327070bdfe9892 SA-CORE-2021-006 by azinck, seanB, effulgentsia, marcoscano, larowlan, phenaproxima, xjm, mcdruid, drumm, briantschu
+ 280194a9f96559dfb356c737967a4b615b754032 SA-CORE-2021-007 by samuel.mortenson, Wim Leers, greggles, xjm, larowlan, vijaycs85, Heine, effulgentsia, phenaproxima, mcdruid, nod_
+ d34d38a93583889c99650b10820f119a466602bf SA-CORE-2021-008 by klausi, xjm, larowlan, alexpott, samuel.mortenson, mcdruid, kim.pepper
+ 948cb5432062fba2112511cca01788127306abd2 SA-CORE-2021-009 by illeace, Wim Leers, xjm, effulgentsia, larowlan, pandaski, vijaycs85, phenaproxima, mcdruid
+ 376c7264064ddb15d9e496035c9eee73d4fd8380 SA-CORE-2021-010 by bradjones1, xjm, bbrala, gabesullice, Wim Leers, e0ipso
+ 4d4e64ff19e7fefad760f223bdb8cf36db9db43e Drupal 9.2.6

$ git cherry -v origin/9.1.x 9.1.13
+ 2a89e7cb90a96c49444d06f5dde472d192bbbba7 SA-CORE-2021-006 by azinck, seanB, effulgentsia, marcoscano, larowlan, phenaproxima, xjm, mcdruid, drumm, briantschu
+ d814501070676aa41636d930e90028b3bb4d95e3 SA-CORE-2021-007 by samuel.mortenson, Wim Leers, greggles, xjm, larowlan, vijaycs85, Heine, effulgentsia, phenaproxima, mcdruid, nod_
+ cd63d0c4f5f41f02d4087b1fdcfa72dafb2bee66 SA-CORE-2021-008 by klausi, xjm, larowlan, alexpott, samuel.mortenson, mcdruid, kim.pepper
+ 181100fd80025fc3577652fb958f696912d7467b SA-CORE-2021-009 by illeace, Wim Leers, xjm, effulgentsia, larowlan, pandaski, vijaycs85, phenaproxima, mcdruid
+ bd3f51b84807abe76668dee57395cb73230b97a1 SA-CORE-2021-010 by bradjones1, xjm, bbrala, gabesullice, Wim Leers, e0ipso
+ bdafd0207e0b6d78baa13ac181d9b74ba5e806cd Drupal 9.1.13

$ git cherry -v origin/8.9.x 8.9.19
+ 92035ee5938c92ea036be5c2429807cb54810454 SA-CORE-2021-006 by azinck, seanB, effulgentsia, marcoscano, larowlan, phenaproxima, xjm, mcdruid, drumm, briantschu
+ 64cf971dd42acc82798179497deaec4a1cd9086e SA-CORE-2021-007 by samuel.mortenson, Wim Leers, greggles, xjm, larowlan, vijaycs85, Heine, effulgentsia, phenaproxima, mcdruid, nod_
+ 6cc64691510c68c9361d457b27eb6f930fe4fefc SA-CORE-2021-008 by klausi, xjm, larowlan, alexpott, samuel.mortenson, mcdruid, kim.pepper
+ d060b3bf421c40193a04e23bc95e5de0577496bf SA-CORE-2021-009 by illeace, Wim Leers, xjm, effulgentsia, larowlan, pandaski, vijaycs85, phenaproxima, mcdruid
+ fd1a9f98583c0b2ef15eedaad48b9abf9fdefd2e SA-CORE-2021-010 by bradjones1, xjm, bbrala, gabesullice, Wim Leers, e0ipso
+ ff4f28f15d717b1ba39867f1550a248d1a915928 Drupal 8.9.19

Setting RTBC, although there is no patch, because core committers are the only ones that can fix this.

9.2.6 also isn't a clean merge any more either. It might be best to recreate the patches for 9.2.x and 9.3.x

9.1.6 would be fine except for the usual version stuff, but getting a js lint error:

~/core/modules/media/js/plugins/drupalmedia/plugin.es6.js
  476:50  error  Insert `⏎···············`  prettier/prettier

✖ 1 problem (1 error, 0 warnings)
  1 error and 0 warnings potentially fixable with the `--fix` option.

@catch if I get a clean checkout of 9.2.x and then cherry-pick each of those commits in order, they merge in cleanly for me:

$ git checkout 9.2.x
$ git reset --hard
$ git pull
$ git cherry-pick 741a4f6bfbfc72202274b56936327070bdfe9892
$ git cherry-pick 280194a9f96559dfb356c737967a4b615b754032
$ git cherry-pick d34d38a93583889c99650b10820f119a466602bf
$ git cherry-pick 948cb5432062fba2112511cca01788127306abd2
$ git cherry-pick 376c7264064ddb15d9e496035c9eee73d4fd8380

After this the only issue is bumping the VERSION constant.

Similarly this works for 9.1.x and 8.9.x.

The attached patch then solves the eslint issue with plugin.es6.js.

Mis-typed about 9.2.x not merging cleanly, too much editing of the comment and took the wrong bit out.

The issue was a CS fail rather than a merge error.

https://www.drupal.org/project/drupal/issues/3238373#comment-14235009 - works great for the js lint issue.

Did the following for the CS error on 9.3.x and 9.2.x:

diff --git a/core/modules/quickedit/tests/src/FunctionalJavascript/LayoutBuilderQuickEditTest.php b/core/modules/quickedit/tests/src/FunctionalJavascript/LayoutBuilderQuickEditTest.php
index 3f49891713..2d48df5b66 100644
--- a/core/modules/quickedit/tests/src/FunctionalJavascript/LayoutBuilderQuickEditTest.php
+++ b/core/modules/quickedit/tests/src/FunctionalJavascript/LayoutBuilderQuickEditTest.php
@@ -128,6 +128,8 @@ public function testQuickEditIgnoresDuplicateFields() {
    *
    * @param bool $use_revisions
    *   If revisions are used.
+   * @param bool $admin_permission
+   *   Whether to grant admin permissions to the user created for the test.
    *
    * @dataProvider providerEnableDisableLayoutBuilder
    */

9.1.x also happy with the merge + patch (no cs fail in the test to fix there), and so was 8.9.x

With 9.3.x, I went ahead and cherry-picked the commits from #8, which all cherry-pick cleanly individually, and better than having to recreate patches. Then I made separate commits for the cs and js lint errors.

I think that is all of it, but would be great if someone could verify all this so leaving RTBC.

Sorry all; this was my fail. I missed that a push failed. Thanks for fixing it!