Deprecate ThemeHandlerInterface::rebuildThemeData() and use extension.list.theme service instead

I have worked a little bit on this much. Did changes at some places and also added @deprecated notice wherever. This patch is only useful once parent issue is fixed. Looking for a good review on this one.
Thanks in advance.

Here's a start. Still need to sort out the ThemeInstaller. Ideally we wouldn't need the ThemeHandler there. But then we'd need to sort out issues with reseting the list in ThemeHandler.

+++ b/core/tests/Drupal/Tests/Core/Extension/ThemeHandlerTest.php
@@ -72,6 +72,8 @@ protected function setUp() {
+   * @group legacy
+   * @expectedDeprecation \Drupal\Core\Extension\ThemeHandlerInterface::rebuildThemeData() is deprecated in Drupal 8.7.0 and will be removed before Drupal 9.0.0. Use \Drupal::service('extension.list.theme')->reset()->getList() instead. See https://www.drupal.org/node/2709919.

Maybe better to create common ThemeHandlerLegacyTest - it will be easy to remove it in 9.0
I'm Adding it in #3017231-4: Properly deprecate ThemeHandlerInterface install() and uninstall() also replace usage

Moved install/uninstall patch to found #2776031-21: Properly deprecate ThemeHandlerInterface install() and uninstall() also replace usage

PS: issues related because also manages how extensions lists are rebuilded/populated

The Needs Review Queue Bot tested this issue. It either no longer applies to Drupal core, or fails the Drupal core commit checks. Therefore, this issue status is now "Needs work".

Apart from a re-roll or rebase, this issue may need more work to address feedback in the issue or MR comments. To progress an issue, incorporate this feedback as part of the process of updating the issue. This helps other contributors to know what is outstanding.

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To answer a question posted in Slack, this needs a separate change record. A change record is for documenting the first version and branch where the change was introduced. When you want to add related issues that can be done in the issue links fields or even in the description body.

For this issue, the changes to the existing change record should move to a new change record. And the new change record can refer to the older one.

I do know the existing change record does not follow what I describe above and it is on my list to update that.

Updated tasks in IS

Left some small comments.

Feedback appears to be addressed.

Includes constructor deprecations for things that need them and doesn't bother for things that don't. Had to read through a couple of times to check, but I think it's a good balance.

Committed/pushed to 11.x and cherry-picked to 10.3.x, thanks!

Published CRs:

• https://www.drupal.org/node/3413308
• https://www.drupal.org/node/3413196

Thank you! the last bit is #2972153: Deprecate ThemeHandlerInterface::getBaseThemes and remove usages from core