IsGenericMethodDefinition needs the same treatment as
IsGenericTypeDefinition, i.e. it should depend on whether the class is a
definition as opposed to merely checking if the type args are generic
parameters (which could happen in a partially specialized method).
Also, array/ref/pointer types of generic types are considered to have
generic parameters, so correct ContainsGenericParameters accordingly.
GenericMethods should contain all MethodSpec-referenced methods,
including those which are non-generic methods inside generic types. This
patch adds those methods, and also implements parameter substitution for
type arguments in parameters & return types.
We're aiming to make TypeInfo instances unique - no two TypeInfo
instances within a given model should refer to the same type. This will
allow us to use simple reference equality for comparing types.
The C# functions for GetGenericParameters/GetGenericArguments use
Type[], not lists, so we should conform to that.
Also fix the definition of IsGenericTypeDefinition - because it's
possible for a class to be instantiated with all generic parameters.
Replace the deeply nested ternaries in TypeInfo with if-statements for
clarity.
Remove in/out from CSharpName, keeping it only on immediate type params
in CSharpTypeDeclarationName (refactored to a method).
Rearrange name-related properties and methods to group them all together
into a region for easier navigation.
