In ilasm/tests:

In ilasm/tests:

	* test-cattr-1.il: New. Test for custom attributes on return type of
	a method.

In ilasm/codegen:

	* MethodDef.cs (MethodDef): Use a ParamDef for return type, instead of a
	BaseTypeRef.
	(MethodDef.ctor): Update.
	(MethodDef.AddParamDefaultValue): Remove.
	(MethodDef.GetParam): Likewise.
	(MethodDef.Resolve): Update to use ret_param instead of ret_type.

In ilasm/errors:

	* err-cattr.il: New.

In ilasm/parser:

	* ILParser.jay (method_decl | D_PARAM ..): Param index is zero-based,
	with zero representing the return value.
	Update to check CurrentCustomAttrTarget for null before using it.

In class/PEAPI:

	* PEAPI.cs (PEFile.AddMethod): Add overload for return type as Param
	instead of PEAPI.Type .
	* Metadata.cs (MetaDataElement.HasCustomAttr): New. Temporary hack.
	(Param.HasMarshalInfo): New.
	(ClassDef.AddMethod): Add overload for return type as Param.
	(MethodDef.ctor): Change internal .ctor's sig to take Param instead of
	PEAPI.Type for return type.
	(MethodDef.retType): Remove.
	(MethodDef.TypeSig): Update to use ret_param always.
	(MethodDef.BuildTables): Add ret_param to Param table only if it has
	marshal info or custom attributes.

git-svn-id: svn+ssh://mono-cvs.ximian.com/source/trunk/mcs@61358 e3ebcda4-bce8-0310-ba0a-eca2169e7518