Enable Moq HostTests on ios

[BrzVlad]

These use some reflection APIs which were not working on trimming enabled workloads. Expand the trimming descriptor for Moq assembly so the required types are preserved.

Fixes #128405

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[Copilot]

Pull request overview

This PR re-enables Moq-based HostTests on Apple mobile CoreCLR by ensuring the linker preserves required Moq/Castle types under aggressive trimming, and by removing the platform-specific ActiveIssue skips.

Changes:

• Added a trimmer root descriptor reference for the shared Castle/Moq linker descriptor in the hosting unit test project.
• Removed [ActiveIssue(...128405...)] from several Moq/Castle-backed HostTests, keeping the IsReflectionEmitSupported gate.
• Expanded ILLink.Descriptors.Castle.xml to preserve the Moq.Async namespace during trimming.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/libraries/Microsoft.Extensions.Hosting/tests/UnitTests/Microsoft.Extensions.Hosting.Unit.Tests.csproj	Adds the shared Castle/Moq trimmer descriptor to the test project so trimmed workloads keep needed types.
src/libraries/Microsoft.Extensions.Hosting/tests/UnitTests/Internal/HostTests.cs	Removes Apple mobile ActiveIssue skips so these Moq-based tests can run again when Reflection.Emit is supported.
eng/testing/ILLinkDescriptors/ILLink.Descriptors.Castle.xml	Roots Moq.Async to prevent trimming from removing reflection-activated async-related Moq types.

Suppressed comments (6)

src/libraries/Microsoft.Extensions.Hosting/tests/UnitTests/Internal/HostTests.cs:663

• Same as above: the comment should match the current gating (Reflection.Emit support + trimmed-workload descriptors) now that these tests are being re-enabled on Apple mobile CoreCLR.

        }

        // Moq heavily utilizes RefEmit, which does not work on most aot workloads
        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsReflectionEmitSupported))]
        public async Task WebHostStopAsyncUsesDefaultTimeoutIfNoTokenProvided()
        {

src/libraries/Microsoft.Extensions.Hosting/tests/UnitTests/Internal/HostTests.cs:630

• Same as above: consider updating this comment to reflect the current reason these tests are guarded (Reflection.Emit support + trimmed-workload descriptors), rather than describing it primarily as an AOT limitation.

        }

        // Moq heavily utilizes RefEmit, which does not work on most aot workloads
        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsReflectionEmitSupported))]
        public async Task HostStopAsyncUsesDefaultTimeoutIfGivenTokenDoesNotFire()
        {

src/libraries/Microsoft.Extensions.Hosting/tests/UnitTests/Internal/HostTests.cs:1220

• Same as above: update this comment to reflect why the tests are conditionally enabled (Reflection.Emit support + trimmed-workload descriptors), to avoid future confusion about Apple mobile support.

        }

        // Moq heavily utilizes RefEmit, which does not work on most aot workloads
        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsReflectionEmitSupported))]
        public void Dispose_DisposesAppConfigurationProviders()
        {

src/libraries/Microsoft.Extensions.Hosting/tests/UnitTests/Internal/HostTests.cs:1245

• Same as above: adjust this comment so it reflects the current reason for the conditional (Reflection.Emit support + trimmed-workload descriptors) rather than primarily calling out AOT.

        }

        // Moq heavily utilizes RefEmit, which does not work on most aot workloads
        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsReflectionEmitSupported))]
        public void Dispose_DisposesHostConfigurationProviders()
        {

src/libraries/Microsoft.Extensions.Hosting/tests/UnitTests/Internal/HostTests.cs:1321

• Same as above: consider updating this comment to align with the current Apple mobile enablement story (Reflection.Emit support + trimmed-workload descriptors).

        }

        // Moq heavily utilizes RefEmit, which does not work on most aot workloads
        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsReflectionEmitSupported))]
        public async Task DisposeAsync_DisposesAppConfigurationProviders()
        {

src/libraries/Microsoft.Extensions.Hosting/tests/UnitTests/Internal/HostTests.cs:1346

• Same as above: now that the ActiveIssue skip is removed, updating this comment helps clarify the intended conditions for these Moq-based tests.

        }

        // Moq heavily utilizes RefEmit, which does not work on most aot workloads
        [ConditionalFact(typeof(PlatformDetection), nameof(PlatformDetection.IsReflectionEmitSupported))]
        public async Task DisposeAsync_DisposesHostConfigurationProviders()
        {