Issue 23481. Fix for creating a new class referenced from an inner local function.

pkg/analysis_server/lib/src/services/correction/fix_internal.dart

Index: pkg/analysis_server/lib/src/services/correction/fix_internal.dart
diff --git a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
index 9e4e8b17c09c6b577f22ddfa6ab4222c6ec4b694..bd00f6cd170da38a4895c3829a5d0b65783166c1 100644
--- a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
+++ b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
@@ -378,7 +378,7 @@ class FixProcessor {
     String name = (node as SimpleIdentifier).name;
     // prepare environment
     CompilationUnitMember enclosingMember =
-        node.getAncestor((node) => node is CompilationUnitMember);
+        node.getAncestor((node) => node.parent is CompilationUnit);
     if (enclosingMember == null) {
       return;
     }