[release/6.0] WinHttp: always read HTTP/2 streams to the end

[github-actions]

Backport of #62870 to release/6.0

Fixes #60291

/cc @antonfirsov

Customer Impact

#60291 is a bug in WinHttpHandler that prevents running/debugging gRPC code on .NET Framework using Visual Studio + IIS Express which is an important customer scenario for dotnet/core#5713. It can probably also manifest in production environments with servers other than Kestrel.

Testing

• Unit tests have been added
• End to end validation of the fix has been done with Visual Studio + IIS Express

Risk

Low. Impacts only specific HTTP/2 cases in WinHttpHandler.

[ghost]

Tagging subscribers to this area: @dotnet/ncl
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Issue Details

---

Backport of #62870 to release/6.0

/cc @antonfirsov

Customer Impact

Testing

Risk

Author:	github-actions[bot]
Assignees:	-
Labels:	area-System.Net
Milestone:	-

[ghost]

Tagging subscribers to this area: @dotnet/ncl
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Backport of #62870 to release/6.0

Fixes #60291

/cc @antonfirsov

Customer Impact

#60291 is a bug in WinHttpHandler that breaks the grpc + WinHttpHandler + IIS scenario. This prevents running/debugging grpc code on .NET Framework using Visual Studio + IIS Express which is an important customer scenario.

Testing

• Unit tests have been added
• End to end validation of the fix has been done with Visual Studio + IIS Express

Risk

Low.

Author:	github-actions[bot]
Assignees:	-
Labels:	Servicing-consider, area-System.Net.Http
Milestone:	-

[karelz]

Note: This PR was insufficient as it forgot NuGet package authoring. The fix was truly released in PR #65523 as part of 6.0.4 (which is WinHttpHandler 6.0.1 to make versioning even more confusing)