VSTHRD010 triggers on method defining delegates that require the main thread

[asundheim]

Bug description

It seems like VSTHRD010 will flag methods that define delegates that call ThreadHelper.ThrowIfNotOnUIThread, though the method itself does not invoke the delegate.

Repro steps

abstract class Foo
{
    Foo()
    {
        this.RefreshCommand = new RelayCommand(
            execute: (object param) => { ThreadHelper.ThrowIfNotOnUIThread(); StartForceRefreshRequest(param); }
            canExecute: (_) => { ThreadHelper.ThrowIfNotOnUIThread(); return CanExecuteForceRefreshCommand(); }
        );
    }
}

class Bar : Foo
{
    Bar() : base()
    {
        // analyzer flags this constructor with the warning:
        // VSTHRD010: Accessing "Foo..ctor" should only be done on the main thread
    }
}

Expected behavior

No threading analyzer warning for the described case.

Actual behavior

Threading analyzer fires warning.

• Version used: latest (v17.11.20)

Additional context

I have not extensively verified the exact conditions for this, but I have verified that removing the thread-affinitized delegate prevents the analyzer warning.