[release/9.0] Fix invalid handle bug happening when TypeBuilder type used in exception catch clause

[github-actions]

Backport of #106665 to release/9.0

/cc @buyaa-n

Customer Impact

• Customer reported
• Found internally

This is found while reviewing PersistedAssemblyBuilder implementation entirely. When newly created TypeBuilder instance is used as exception type, when ILGenerator.BeginCatchBlock(Type? exceptionType) called ILGenerator will throw because the TypeBuilder token is invalid, it works fine when existing exception types used.

Root cause:

A newly created TypeBuilder token is not valid when ILGenerator.BeginCatchBlock(Type? exceptionType) called and the token will not be populated properly until the assembly saved into a file or stream.

Solution

Instead of adding exception handler blocks directly into the ControlFlowBuilder instance, now collecting them into a list and adding them to the ControlFlowBuilder during Save where all tokens will have populated properly.

Regression

• Yes
• No

It is a bug in a new PersistedAssemblyBuilder added in .NET 9

Testing

A unit test added that reproes the issue

Risk

Low, the fix is straight forward and clean, should not cause a regression

Side note

No new API added with the PR, instead if removed an overriden API from ref that is not needed to be overriden

[dotnet-issue-labeler]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[dotnet-issue-labeler]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

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[steveharter]

FYI some unrelated errors in Build Analysis.

[jeffhandley]

Once this is green, it's approved for merge into RC2 as it's a bug in a new feature in .NET 9.

[buyaa-n]

/ba-g no failure related to PR or unknown

FYI: @carlossanlop

[artl93]

M2 approved