Fix how root provider resolve generic methods

[hez2010]

• There may be multiple candidate generic methods available, ilc shouldn't throw exceptions when it meets the first unmatched method.
• To improve diagnosability I also append generic parameters to failure output.
• Matching methods containing signature variables

Contributes to #733

[hez2010]

I think it's better to do matching for signature variables, but it seems that the correct approach is not as simple as the implementation in 2eef27e, so I want to skip it for now.

Update: Done.

[hez2010]

@MichalStrehovsky I've added support to match all parameters, and I've tested it with below code:

using System;
using System.Collections.Generic;

namespace DimRepro
{
    unsafe interface ITest<T>
    {
        void Bar(string baz) => Console.WriteLine(baz);
        void Bar(T what, string baz) => Console.WriteLine(what.ToString() + baz);
        void Bar<U>(U what, string baz, List<T> how) => Console.WriteLine(what.ToString() + how.ToString() + baz);
        void Bar<U>(U[] what, string baz, List<T> how) => Console.WriteLine(what.ToString() + how.ToString() + baz);
        void Bar<U>(List<T> what, string baz, List<U> how) => Console.WriteLine(what.ToString() + how.ToString() + baz);
        void Bar<U>(List<U[]> what, string baz, List<T> how) => Console.WriteLine(what.ToString() + how.ToString() + baz);
        void Bar<U>(Dictionary<U, T> what, string baz, List<T> how) => Console.WriteLine(what.ToString() + how.ToString() + baz);
    }

    class Test<T> : ITest<T> { }

    class Program
    {
        static void Main(string[] args)
        {
            ITest<float> x = new Test<float>();
            x.Bar("test");
            x.Bar(5, "test");
            x.Bar(5, "hello", new List<float>());
            x.Bar(new[] { 5 }, "hello", new List<float>());
            x.Bar(new List<float> { 5f }, "hello", new List<string>());
            x.Bar(new List<int[]> { new[] { 5 } }, "hello", new List<float>());
            x.Bar(new Dictionary<int, float>(), "hello", new List<float>());
        }
    }
}

rd.xml:

<Directives>
    <Application>
        <Assembly Name="DimRepro">
            <Type Name="DimRepro.ITest`1[[System.Single,System.Private.CoreLib]]" Dynamic="Required All">
                <Method Name="Bar" Dynamic="Required">
                    <Parameter Name="System.Single,System.Private.CoreLib" />
                    <Parameter Name="System.String,System.Private.CoreLib" />
                </Method>
                <Method Name="Bar" Dynamic="Required">
                    <GenericArgument Name="System.Int32,System.Private.CoreLib" />
                    <Parameter Name="System.Int32,System.Private.CoreLib" />
                    <Parameter Name="System.String,System.Private.CoreLib" />
                    <Parameter Name="System.Collections.Generic.List`1[[System.Single,System.Private.CoreLib]],System.Private.CoreLib" />
                </Method>
                <Method Name="Bar" Dynamic="Required">
                    <GenericArgument Name="System.Int32,System.Private.CoreLib" />
                    <Parameter Name="System.Int32[],System.Private.CoreLib" />
                    <Parameter Name="System.String,System.Private.CoreLib" />
                    <Parameter Name="System.Collections.Generic.List`1[[System.Single,System.Private.CoreLib]],System.Private.CoreLib" />
                </Method>
                <Method Name="Bar" Dynamic="Required">
                    <GenericArgument Name="System.Int32,System.Private.CoreLib" />
                    <Parameter Name="System.Collections.Generic.List`1[[System.Single,System.Private.CoreLib]],System.Private.CoreLib" />
                    <Parameter Name="System.String,System.Private.CoreLib" />
                    <Parameter Name="System.Collections.Generic.List`1[[System.Int32,System.Private.CoreLib]],System.Private.CoreLib" />
                </Method>
                <Method Name="Bar" Dynamic="Required">
                    <GenericArgument Name="System.Int32,System.Private.CoreLib" />
                    <Parameter Name="System.Collections.Generic.List`1[[System.Int32[],System.Private.CoreLib]],System.Private.CoreLib" />
                    <Parameter Name="System.String,System.Private.CoreLib" />
                    <Parameter Name="System.Collections.Generic.List`1[[System.Single,System.Private.CoreLib]],System.Private.CoreLib" />
                </Method>
                <Method Name="Bar" Dynamic="Required">
                    <GenericArgument Name="System.Int32,System.Private.CoreLib" />
                    <Parameter Name="System.Collections.Generic.Dictionary`2[[System.Int32,System.Private.CoreLib],[System.Single,System.Private.CoreLib]],System.Private.CoreLib" />
                    <Parameter Name="System.String,System.Private.CoreLib" />
                    <Parameter Name="System.Collections.Generic.List`1[[System.Single,System.Private.CoreLib]],System.Private.CoreLib" />
                </Method>
            </Type>
            <Type Name="DimRepro.Test`1[[System.Single,System.Private.CoreLib]]" Dynamic="Required All" />
        </Assembly>

    </Application>
</Directives>

[hez2010]

I think this PR is ready. rd.xml documents may need updates later.

[MichalStrehovsky]

Thank you!