Annotating System.Diagnostics.DiagnosticSource on AOT

[LakshanF]

There are 2 leaf level warnings

• In Internal class PropertySpec, FetcherForProperty has 2 MakeGenericType warnings. The RDC warnings are propagated for root APIs in the assembly with the following exceptions

OnEventWritten, similar to the RUC suppression message, DiagnosticSource.Write is now annotated with RDC

OnActivityStarted, since Activity is a reference type and MakeGenericType is safe

OnActivityStopped, since Activity is a reference type and MakeGenericType is safe.

AllListeners get method since the dangerous HttpHandlerDiagnosticListener static is only enabled in older .NET FX

• The internal Aggregate types warning at BuildInstrumentState is suppressed

[LakshanF]

/azp run runtime-extra-platforms

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