Fix initial namespace population

src/Features/CSharp/Portable/MoveToNamespace/CSharpMoveToNamespaceService.cs

@@ -18,5 +18,10 @@ public CSharpMoveToNamespaceService(IMoveToNamespaceOptionsService moveToNamespa
             : base(moveToNamespaceOptionsService)
         {
         }
+
+        protected override string GetNamespaceName(NamespaceDeclarationSyntax syntax)
+        {
+            return syntax.Name.ToString();
+        }
     }
 }

src/Features/Core/Portable/MoveToNamespace/AbstractMoveToNamespaceService.cs

@@ -27,6 +27,8 @@ internal abstract class AbstractMoveToNamespaceService<TCompilationSyntax, TName
     {
         private IMoveToNamespaceOptionsService _moveToNamespaceOptionsService;
 
+        protected abstract string GetNamespaceName(TNamespaceDeclarationSyntax syntax);
+
         public AbstractMoveToNamespaceService(IMoveToNamespaceOptionsService moveToNamespaceOptionsService)
         {
             _moveToNamespaceOptionsService = moveToNamespaceOptionsService;
@@ -70,7 +72,8 @@ public AbstractMoveToNamespaceService(IMoveToNamespaceOptionsService moveToNames
                     return new MoveToNamespaceAnalysisResult("Container contains nested namespace declaration");
                 }
 
-                return new MoveToNamespaceAnalysisResult(document, node, declarationSyntax.GetTypeDisplayName());
+                var @namespace = symbol?.Name ?? GetNamespaceName(declarationSyntax);
+                return new MoveToNamespaceAnalysisResult(document, node, @namespace);
             }
 
             return new MoveToNamespaceAnalysisResult("Not a valid position");