Update TeachingTip to use XamlRootChanged_revoker

[kmahone]

There is an issue with the XamlRoot Changed event handler that results in the C++/WinRT auto_revoker not working as expected. This had the effect that the event handler was not being revoked in TeachingTip and when the XamlRoot.Changed event fired, we would raise the event on a potentially deleted TeachingTip. This is causing crashes in apps.

The solution is to use a custom implementation of XamlRootChanged_revoker.

The underlying issue with the XamlRoot.Changed event is tracked by OS Bug 21302432.

[kmahone]

/azp run

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[RBrid]

I think SwipeControl is using the old code too:
m_xamlRootChangedRevoker = xamlRoot.Changed(winrt::auto_revoke, { this, &SwipeControl::CurrentXamlRootChanged });

Maybe it's worth changing it too?

[kmahone]

I think SwipeControl is using the old code too: m_xamlRootChangedRevoker = xamlRoot.Changed(winrt::auto_revoke, { this, &SwipeControl::CurrentXamlRootChanged });

Maybe it's worth changing it too?

Let me fix that too.

[kmahone]

I think SwipeControl is using the old code too: m_xamlRootChangedRevoker = xamlRoot.Changed(winrt::auto_revoke, { this, &SwipeControl::CurrentXamlRootChanged });
Maybe it's worth changing it too?

Let me fix that too.

Fixed SwipeControl also.

[kmahone]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[ghost]

🎉Microsoft.UI.Xaml v2.8.0-prerelease.220413001 has been released which incorporates this pull request.:tada:

Handy links:

• Release Notes
• Official Nuget Release

[ghost]

🎉Microsoft.UI.Xaml v2.8.0-prerelease.220712001 has been released which incorporates this pull request.:tada:

Handy links:

• Release Notes
• Official Nuget Release

[ghost]

🎉Microsoft.UI.Xaml v2.8.0 has been released which incorporates this pull request.:tada:

Handy links:

• Release Notes
• Official Nuget Release

[ghost]

🎉Microsoft.UI.Xaml v2.8.2 has been released which incorporates this pull request.:tada:

Handy links:

• Release Notes
• Official Nuget Release