message: style: emove unreachable 'return null' statement
  There's another return statement before this one, therefore 'return null' will never be reached.
  PR Close
diff: @@ -68,7 +68,6 @@ export class UndecoratedParentMigration implements Migration {
  return makeDiagnostic(
  ErrorCode.NGCC_MIGRATION_EXTERNAL_BASE_CLASS, baseClassExpr,
  `${clazz.name.text} class has a dynamic base class ${baseClassExpr.getText()}, so it is not possible to migrate.`);
  - return null;
  }
  const baseClazz = host.reflectionHost.getDeclarationOfIdentifier(baseClassExpr) !.node;
  