Use SRM's TypeName parser in ILLink (#103740)

This replaces the type name parser we copied from corert with the one
in System.Reflection.Metadata.

Adds a test for resolving escaped type names, shared by ILLink and
Native AOT. To support this testcase, the test infra also uses
TypeNameResolver. The ILLink tests use it via IVT, and the Native AOT
tests use it by including source files. The sources have been factored
a little to make it possible to use just the TypeNameResolver from
NativeAot without pulling in other components of ILLink.

src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/Logging/DocumentationSignatureGenerator.PartVisitor.cs

@@ -8,8 +8,7 @@
 
 namespace ILCompiler.Logging
 {
-
-    public sealed partial class DocumentationSignatureGenerator
+    internal sealed partial class DocumentationSignatureGenerator
     {
         /// <summary>
         ///  A visitor that generates the part of the documentation comment after the initial type

src/coreclr/tools/aot/ILCompiler.Trimming.Tests/ILCompiler.Trimming.Tests.csproj

@@ -24,6 +24,14 @@
     <ProjectReference Include="../ILCompiler.RyuJit/ILCompiler.RyuJit.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <Compile Include="$(ToolsProjectRoot)illink/src/linker/Linker/TypeNameResolver.cs" />
+    <Compile Include="$(ToolsProjectRoot)illink/src/linker/Linker/ITryResolve.cs" />
+    <Compile Include="$(ToolsProjectRoot)illink/src/linker/Linker/ModuleDefinitionExtensions.cs" />
+    <Compile Include="$(LibrariesProjectRoot)/Common/src/System/Reflection/Metadata/TypeNameHelpers.cs" />
+    <Compile Include="$(LibrariesProjectRoot)/Common/src/System/Text/ValueStringBuilder.cs" />
+  </ItemGroup>
+
   <ItemGroup>
     <RuntimeHostConfigurationOption Include="Mono.Linker.Tests.RuntimeBinDirectory">
       <Value>$(RuntimeBinDir)</Value>

src/coreclr/tools/aot/ILCompiler.Trimming.Tests/TestCasesRunner/AssemblyChecker.cs

@@ -37,6 +37,7 @@ class LinkedMethodEntity : LinkedEntity
 		}
 
 		private readonly BaseAssemblyResolver originalsResolver;
+		private readonly TypeNameResolver originalsTypeNameResolver;
 		private readonly ReaderParameters originalReaderParameters;
 		private readonly AssemblyDefinition originalAssembly;
 		private readonly TrimmedTestCaseResult testResult;
@@ -69,6 +70,7 @@ public AssemblyChecker (
 			TrimmedTestCaseResult testResult)
 		{
 			this.originalsResolver = originalsResolver;
+			this.originalsTypeNameResolver = new TypeNameResolver (new TestResolver (), new TestAssemblyNameResolver (originalsResolver));
 			this.originalReaderParameters = originalReaderParameters;
 			this.originalAssembly = original;
 			this.testResult = testResult;
@@ -1468,7 +1470,9 @@ internal IEnumerable<string> VerifyLinkingOfOtherAssemblies (AssemblyDefinition
 						}
 
 						var expectedTypeName = checkAttrInAssembly.ConstructorArguments[1].Value.ToString ()!;
-						var expectedType = originalTargetAssembly.MainModule.GetType(expectedTypeName);
+						if (!originalsTypeNameResolver.TryResolveTypeName (originalTargetAssembly, expectedTypeName, out TypeReference? expectedTypeRef, out _))
+							Assert.Fail($"Could not resolve original type `{expectedTypeName}' in assembly {assemblyName}");
+						TypeDefinition expectedType = expectedTypeRef.Resolve ();
 						linkedMembersInAssembly.TryGetValue(new AssemblyQualifiedToken(expectedType), out LinkedEntity? linkedTypeEntity);
 						MetadataType? linkedType = linkedTypeEntity?.Entity as MetadataType;