Enable Finalizer event in NativeAOT

[LakshanF]

The finalizer thread in NativeAOT is in managed code and should fire events similar to the CoreCLR native implementation.

The managed code in NativeAOT for this is in the base class library, as opposed to the CoreLib implementation for exception event and require investigation on the RuntimeImport support to enable the event.

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Issue Details

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The finalizer thread in NativeAOT is in managed code and should fire events similar to the CoreCLR native implementation.

The managed code in NativeAOT for this is in the base class library, as opposed to the CoreLib implementation for exception event and require investigation on the RuntimeImport support to enable the event.

Author:	LakshanF
Assignees:	LakshanF
Labels:	area-NativeAOT-coreclr
Milestone:	8.0.0

[MichalStrehovsky]

If we need to fire an event at the beginning/end, the implementation being in managed doesn't matter:

runtime/src/coreclr/nativeaot/Runtime.Base/src/System/Runtime/__Finalizer.cs

Lines 30 to 37 in 6d6fbe0

	if (InternalCalls.RhpWaitForFinalizerRequest() != 0)
	{
	DrainQueue();
	// Tell anybody that's interested that the finalization pass is complete (there is a race condition here
	// where we might immediately signal a new request as complete, but this is acceptable).
	InternalCalls.RhpSignalFinalizationComplete();
	}

RhpWaitForFinalizerRequest and RhpSignalFinalizationComplete are in native and we can call into eventpipe easily from there. We can add a parameter to RhpSignalFinalizationComplete with the number of finalized objects.