fix(cdk/scrolling): adds ngTemplateContextGuard

[naaajii]

implements ngTemplateContextGuard for
CdkVirtualForOf directive

fixes #26609

[crisbeto]

The change LGTM, but this is a breaking change so it'll have to wait until v17.

[crisbeto]

Caretaker note: the stronger typings cause a lot of broken builds internally.

[studioromeo]

Hello. I just wanted to ask what the new milestone is for this PR since v17 has been released. Thanks!

[JorisMolnar]

I would like to repeat the question. This PR currently has no milestone. Are you planning on merging this for some major version?

[crisbeto]

We do want to merge it eventually, but we haven't had the bandwidth to debug the breakages internally. An option can be to patch out these changes internally so it can at least land externally.

[angular-automatic-lock-bot]

This issue has been automatically locked due to inactivity.
Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

_{This action has been performed automatically by a bot.}