Add missing TypeForwardedFromAttribute to System.Drawing serializable types

[safern]

We missed this attributes when made this types serializable.

FYI: @Tanya-Solyanik

[ericstj]

LGTM, assuming its complete.

[danmoseley]

Fine to add but wasn't there discussion about only supporting binary serialization of these drawing types between CoreFX and CoreFX - these attributes are presumably only necessary when .NET Framework did the serialization. Perhaps I misremember.

[ViktorHofer]

I guess that's required for WinForms resource deserialization?

[Tanya-Solyanik]

This might be required for resx, but this is also required for other desktop interop scenarios.

[ericstj]

these attributes are presumably only necessary when .NET Framework did the serialization.

It's actually the other way around. TypeForwardedTo handles the case where netframework did the serialization. TypeForwardedFrom handles the case where netcore does the serialization (and netframework does the de-serialization).

+1 to resx, it will be required assuming the resgen doesn't change.

[safern]

test Linux arm64 Release Build please

[stephentoub]

Thanks, @safern.