Meta-issue: tracking improvements from CsWinRT's adoption

[Sergio0694]

Problem Description

We're adopting AsmResolver for CsWinRT, and this issue is meant to be a general tracking issue for all kinds of small improvements and ideas that come up as we continue using the library in our interop generator (as suggested by @Washi1337 on Discord).

Items are in no particular order.

Bugs (blockers)

• Fix not fully qualified type names in blobs #648
• TypeSignatures for nested types are incorrectly encoded as CA argument blobs #665

Missing UTF8 overloads

• AsmResolver.DotNet.HasCustomAttributeExtensions.HasCustomAttribute
• CreateTypeReference overloads (in TypeDescriptorExtensions)
• CreateMemberReference overloads (in TypeDescriptorExtensions)
• ModuleDefinition constructor also taking a corelib

Validation ideas

• Throw if a MethodDescription is created with the .Static attribute using an instance signature, or vice versa
• Throw if using MakeStandAloneSignature on a function pointer signature, rather on the target method definition directly
• Throw if making a signature with void as a parameter

[Washi1337]

Some notes on the metadata validation suggestions:

Throw if a MethodDescription is created with the .Static attribute using an instance signature, or vice versa

We can probably add this directly to the constructor of MethodDefinition, but also still allowing null to allow for invalid or custom metadata to be constructed:

AsmResolver/src/AsmResolver.DotNet/MethodDefinition.cs

Lines 70 to 76 in 07d0244

	public MethodDefinition(Utf8String? name, MethodAttributes attributes, MethodSignature? signature)
	: this(new MetadataToken(TableIndex.Method, 0))
	{
	Name = name;
	Attributes = attributes;
	Signature = signature;
	}

Throw if using MakeStandAloneSignature on a function pointer signature, rather on the target method definition directly

I think this should not be checked in MakeStandAloneSignature. StandAloneSignatures can also wrap other types of blob signatures (even ones with custom formats). Furthermore, AsmResolver should also be able to write "invalid" method bodies as well.

I propose we add the check directly on the CIL instruction stream itself, i.e., in the Insert method:

AsmResolver/src/AsmResolver.DotNet/Code/Cil/CilInstructionCollection.Insert.cs

Lines 391 to 397 in 07d0244

	public CilInstruction Insert(int index, CilOpCode code, StandAloneSignature signature)
	{
	if (code.OperandType != CilOperandType.InlineSig)
	throw new InvalidCilInstructionException(code);
	return InsertAndReturn(index, code, signature);
	}