anchor.diff:  
   import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
   import 'package:analysis_server/src/services/completion/dart/keyword_contributor.dart';
  +import 'package:analyzer/dart/analysis/features.dart';
   import 'package:analyzer/dart/ast/token.dart';
   import 'package:analyzer/src/dart/analysis/experiments.dart';
   import 'package:analyzer_plugin/protocol/protocol_common.dart';
  
positive.code:     Keyword.TRUE,
    ];
  
    List<Keyword> get classBodyKeywords => [
          Keyword.CONST,
          Keyword.COVARIANT,
          Keyword.DYNAMIC,
          Keyword.FACTORY,
          Keyword.FINAL,
          Keyword.GET,
          Keyword.OPERATOR,
          Keyword.SET,
          Keyword.STATIC,
          Keyword.VAR,
          Keyword.VOID
        ];
  
    List<Keyword> get constructorParameter => [Keyword.COVARIANT, Keyword.THIS];
  
    List<Keyword> get declarationKeywords => [
          Keyword.ABSTRACT,
          Keyword.CLASS,
          Keyword.CONST,
          Keyword.COVARIANT,
          Keyword.DYNAMIC,
          Keyword.FINAL,
          Keyword.TYPEDEF,
          Keyword.VAR,
          Keyword.VOID
        ];
  
    List<Keyword> get directiveAndDeclarationKeywords => [
          Keyword.ABSTRACT,
          Keyword.CLASS,
          Keyword.CONST,
          Keyword.COVARIANT,
          Keyword.DYNAMIC,
          Keyword.EXPORT,
          Keyword.FINAL,
          Keyword.IMPORT,
          Keyword.PART,
          Keyword.TYPEDEF,
          Keyword.VAR,
          Keyword.VOID
        ];
  
    List<Keyword> get directiveDeclarationAndLibraryKeywords =>
        directiveDeclarationKeywords..add(Keyword.LIBRARY);
  
    List<Keyword> get directiveDeclarationKeywords => [
          Keyword.ABSTRACT,
          Keyword.CLASS,
          Keyword.CONST,
          Keyword.COVARIANT,
          Keyword.DYNAMIC,
          Keyword.EXPORT,
          Keyword.FINAL,
          Keyword.IMPORT,
          Keyword.PART,
          Keyword.TYPEDEF,
          Keyword.VAR,
          Keyword.VOID
        ];
  
    List<Keyword> get methodParameter => [Keyword.COVARIANT];
  
    List<Keyword> get statementStartInClass => [
          Keyword.ASSERT,
          Keyword.CONST,
          Keyword.DO,
          Keyword.FINAL,
          Keyword.FOR,
          Keyword.IF,
          Keyword.NEW,
          Keyword.RETURN,
          Keyword.SUPER,
          Keyword.SWITCH,
          Keyword.THIS,
          Keyword.THROW,
          Keyword.TRY,
          Keyword.VAR,
          Keyword.VOID,
          Keyword.WHILE
        ];
  
    List<Keyword> get statementStartInLoopInClass => [
          Keyword.ASSERT,
          Keyword.BREAK,
          Keyword.CONST,
          Keyword.CONTINUE,
          Keyword.DO,
          Keyword.FINAL,
          Keyword.FOR,
          Keyword.IF,
          Keyword.NEW,
          Keyword.RETURN,
          Keyword.SUPER,
          Keyword.SWITCH,
          Keyword.THIS,
          Keyword.THROW,
          Keyword.TRY,
          Keyword.VAR,
          Keyword.VOID,
          Keyword.WHILE
        ];
  
    List<Keyword> get statementStartInLoopOutsideClass => [
          Keyword.ASSERT,
          Keyword.BREAK,
          Keyword.CONST,
          Keyword.CONTINUE,
          Keyword.DO,
          Keyword.FINAL,
          Keyword.FOR,
          Keyword.IF,
          Keyword.NEW,
          Keyword.RETURN,
          Keyword.SWITCH,
          Keyword.THROW,
          Keyword.TRY,
          Keyword.VAR,
          Keyword.VOID,
          Keyword.WHILE
        ];
  
    List<Keyword> get statementStartInSwitchCaseInClass => [
          Keyword.ASSERT,
          Keyword.BREAK,
          Keyword.CONST,
          Keyword.DO,
          Keyword.FINAL,
          Keyword.FOR,
          Keyword.IF,
          Keyword.NEW,
          Keyword.RETURN,
          Keyword.SUPER,
          Keyword.THIS,
          Keyword.SWITCH,
          Keyword.THROW,
          Keyword.TRY,
          Keyword.VAR,
          Keyword.VOID,
          Keyword.WHILE
        ];
  
    List<Keyword> get statementStartInSwitchCaseOutsideClass => [
          Keyword.ASSERT,
          Keyword.BREAK,
          Keyword.CONST,
          Keyword.DO,
          Keyword.FINAL,
          Keyword.FOR,
          Keyword.IF,
          Keyword.NEW,
          Keyword.RETURN,
          Keyword.SWITCH,
          Keyword.THROW,
          Keyword.TRY,
          Keyword.VAR,
          Keyword.VOID,
          Keyword.WHILE
        ];
  
    List<Keyword> get statementStartInSwitchInClass => [
          Keyword.ASSERT,
          Keyword.BREAK,
          Keyword.CASE,
          Keyword.CONST,
          Keyword.DEFAULT,
          Keyword.DO,
          Keyword.FINAL,
          Keyword.FOR,
          Keyword.IF,
          Keyword.NEW,
          Keyword.RETURN,
          Keyword.SUPER,
          Keyword.SWITCH,
          Keyword.THIS,
          Keyword.THROW,
          Keyword.TRY,
          Keyword.VAR,
          Keyword.VOID,
          Keyword.WHILE
        ];
  
    List<Keyword> get statementStartInSwitchOutsideClass => [
          Keyword.ASSERT,
          Keyword.BREAK,
          Keyword.CASE,
          Keyword.CONST,
          Keyword.DEFAULT,
          Keyword.DO,
          Keyword.FINAL,
          Keyword.FOR,
          Keyword.IF,
          Keyword.NEW,
          Keyword.RETURN,
          Keyword.SWITCH,
          Keyword.THROW,
          Keyword.TRY,
          Keyword.VAR,
          Keyword.VOID,
          Keyword.WHILE
        ];
  
    List<Keyword> get statementStartOutsideClass => [
          Keyword.ASSERT,
          Keyword.CONST,
          Keyword.DO,
          Keyword.FINAL,
          Keyword.FOR,
          Keyword.IF,
          Keyword.NEW,
          Keyword.RETURN,
          Keyword.SWITCH,
          Keyword.THROW,
          Keyword.TRY,
          Keyword.VAR,
          Keyword.VOID,
          Keyword.WHILE
        ];
  
    List<Keyword> get staticMember =>
        [Keyword.CONST, Keyword.COVARIANT, Keyword.FINAL];
  
    void assertSuggestKeywords(Iterable<Keyword> expectedKeywords,
        {List<String> pseudoKeywords = NO_PSEUDO_KEYWORDS,
  
negative.code: @reflectiveTest
  class KeywordContributorWithNnbdTest extends KeywordContributorTest {
    @override
    void setupResourceProvider() {
      super.setupResourceProvider();
      createAnalysisOptionsFile(experiments: [EnableString.non_nullable]);
  