Variable naming doesn't find all accessible types with lower case names

[ds5678]

Input code

using System;
using System.Runtime.InteropServices;

namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
{
	internal static class Issue4000
	{
		[StructLayout(LayoutKind.Sequential, Size = 1)]
		public readonly struct fsResult
		{
			public static fsResult Success => default(fsResult);
			public static fsResult Failure => default(fsResult);
			public bool Succeeded => true;
			public bool Failed => false;
			public static fsResult operator +(fsResult a, fsResult b)
			{
				return default(fsResult);
			}
		}

		public static fsResult M()
		{
			fsResult success = fsResult.Success;
			fsResult fsResult2 = success + fsResult.Success;
			if (fsResult2.Succeeded)
			{
				return success;
			}
			Console.WriteLine("Failed");
			return fsResult2 + fsResult.Failure;
		}
	}
}

Erroneous output

using System;
using System.Runtime.InteropServices;

namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
{
	internal static class Issue4000
	{
		[StructLayout(LayoutKind.Sequential, Size = 1)]
		public readonly struct fsResult
		{
			public static fsResult Success => default(fsResult);
			public static fsResult Failure => default(fsResult);
			public bool Succeeded => true;
			public bool Failed => false;
			public static fsResult operator +(fsResult a, fsResult b)
			{
				return default(fsResult);
			}
		}

		public static fsResult M()
		{
			fsResult success = fsResult.Success;
			fsResult fsResult = success + fsResult.Success;
			if (fsResult.Succeeded)
			{
				return success;
			}
			Console.WriteLine("Failed");
			return fsResult + fsResult.Failure;
		}
	}
}

CS0841: Cannot use local variable 'fsResult' before it is declared

Details

• Product in use: ILSpy
• Version in use: 61f82d0
• Any other relevant information to the issue, or your interest in contributing a fix.
  • I've implemented a fix in AssignVariableNames and am polishing it up for a pull request.