Delete debug-only reference validation

This was some legacy code that tried to verify that the references
we have from the project system match up to what DTE and other sources
say. This was debug-only, and the actual asserts were commented out.
This is deadweight at this point, so delete it.

src/VisualStudio/Core/Def/Implementation/ProjectSystem/AbstractProject.cs

@@ -280,18 +280,8 @@ protected string ContainingDirectoryPathOpt
 
         internal VsENCRebuildableProjectImpl EditAndContinueImplOpt { get; private set; }
 
-        /// <summary>
-        /// Override this method to validate references when creating <see cref="ProjectInfo"/> for current state.
-        /// By default, this method does nothing.
-        /// </summary>
-        protected virtual void ValidateReferences()
-        {
-        }
-
         public ProjectInfo CreateProjectInfoForCurrentState()
         {
-            ValidateReferences();
-
             lock (_gate)
             {
                 var info = ProjectInfo.Create(
@@ -1474,16 +1464,6 @@ private static MetadataReferenceResolver CreateMetadataReferenceResolver(IMetada
             return new WorkspaceMetadataFileReferenceResolver(metadataService, new RelativePathResolver(assemblySearchPaths, baseDirectory: projectDirectory));
         }
 
-#if DEBUG
-        public virtual bool Debug_VBEmbeddedCoreOptionOn
-        {
-            get
-            {
-                return false;
-            }
-        }
-#endif
-
         /// <summary>
         /// Used for unit testing: don't crash the process if something bad happens.
         /// </summary>

src/VisualStudio/Core/Def/Implementation/ProjectSystem/Legacy/AbstractLegacyProject.cs

@@ -169,94 +169,5 @@ private static bool GetIsWebsiteProject(IVsHierarchy hierarchy)
 
             return false;
         }
-
-        protected sealed override void ValidateReferences()
-        {
-            ValidateReferencesCore();
-        }
-
-        [Conditional("DEBUG")]
-        private void ValidateReferencesCore()
-        {
-            // can happen when project is unloaded and reloaded or in Venus (aspx) case
-            if (ProjectFilePath == null || BinOutputPath == null || ObjOutputPath == null)
-            {
-                return;
-            }
-
-            if (ErrorHandler.Failed(Hierarchy.GetProperty(VSConstants.VSITEMID_ROOT, (int)__VSHPROPID.VSHPROPID_ExtObject, out var property)))
-            {
-                return;
-            }
-
-            var dteProject = property as EnvDTE.Project;
-            if (dteProject == null)
-            {
-                return;
-            }
-
-            var vsproject = dteProject.Object as VSProject;
-            if (vsproject == null)
-            {
-                return;
-            }
-
-            var noReferenceOutputAssemblies = new List<string>();
-            var factory = this.ServiceProvider.GetService(typeof(SVsEnumHierarchyItemsFactory)) as IVsEnumHierarchyItemsFactory;
-            if (ErrorHandler.Failed(factory.EnumHierarchyItems(Hierarchy, (uint)__VSEHI.VSEHI_Leaf, (uint)VSConstants.VSITEMID.Root, out var items)))
-            {
-                return;
-            }
-
-            VSITEMSELECTION[] item = new VSITEMSELECTION[1];
-            while (ErrorHandler.Succeeded(items.Next(1, item, out var fetched)) && fetched == 1)
-            {
-                // ignore ReferenceOutputAssembly=false references since those will not be added to us in design time.
-                var storage = Hierarchy as IVsBuildPropertyStorage;
-                storage.GetItemAttribute(item[0].itemid, "ReferenceOutputAssembly", out var value);
-                Hierarchy.GetProperty(item[0].itemid, (int)__VSHPROPID.VSHPROPID_Caption, out var caption);
-
-                if (string.Equals(value, "false", StringComparison.OrdinalIgnoreCase) ||
-                    string.Equals(value, "off", StringComparison.OrdinalIgnoreCase) ||
-                    string.Equals(value, "0", StringComparison.OrdinalIgnoreCase))
-                {
-                    noReferenceOutputAssemblies.Add((string)caption);
-                }
-            }
-
-            var projectReferences = GetCurrentProjectReferences();
-            var metadataReferences = GetCurrentMetadataReferences();
-            var set = new HashSet<string>(vsproject.References.OfType<Reference>().Select(r => PathUtilities.IsAbsolute(r.Name) ? Path.GetFileNameWithoutExtension(r.Name) : r.Name), StringComparer.OrdinalIgnoreCase);
-            var delta = set.Count - noReferenceOutputAssemblies.Count - (projectReferences.Length + metadataReferences.Length);
-            if (delta == 0)
-            {
-                return;
-            }
-
-            // okay, two has different set of dlls referenced. check special Microsoft.VisualBasic case.
-            if (delta != 1)
-            {
-                //// Contract.Requires(false, "different set of references!!!");
-                return;
-            }
-
-            set.ExceptWith(noReferenceOutputAssemblies);
-            set.ExceptWith(projectReferences.Select(r => ProjectTracker.GetProject(r.ProjectId).DisplayName));
-            set.ExceptWith(metadataReferences.Select(m => Path.GetFileNameWithoutExtension(m.FilePath)));
-
-            //// Contract.Requires(set.Count == 1);
-
-            var reference = set.First();
-            if (!string.Equals(reference, "Microsoft.VisualBasic", StringComparison.OrdinalIgnoreCase))
-            {
-                //// Contract.Requires(false, "unknown new reference " + reference);
-                return;
-            }
-
-#if DEBUG
-            // when we are missing microsoft.visualbasic reference, make sure we have embedded vb core option on.
-            Contract.Requires(Debug_VBEmbeddedCoreOptionOn);
-#endif
-        }
     }
 }

src/VisualStudio/VisualBasic/Impl/ProjectSystemShim/VisualBasicProject.vb

@@ -502,13 +502,5 @@ Namespace Microsoft.VisualStudio.LanguageServices.VisualBasic.ProjectSystemShim
                 SetOptions(lastCompilationOptions.WithGlobalImports(_imports), CurrentParseOptions)
             End If
         End Sub
-
-#If DEBUG Then
-        Public Overrides ReadOnly Property Debug_VBEmbeddedCoreOptionOn As Boolean
-            Get
-                Return DirectCast(CurrentCompilationOptions, VisualBasicCompilationOptions).EmbedVbCoreRuntime
-            End Get
-        End Property
-#End If
     End Class
 End Namespace