| Index: pkg/analyzer/lib/src/fasta/ast_builder.dart
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| diff --git a/pkg/analyzer/lib/src/fasta/ast_builder.dart b/pkg/analyzer/lib/src/fasta/ast_builder.dart
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| index 82acfca7cfb32394398ea67f48b7639bbf7a46f0..72411017fdae047d7dbc880329133ae83326a742 100644
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| --- a/pkg/analyzer/lib/src/fasta/ast_builder.dart
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| +++ b/pkg/analyzer/lib/src/fasta/ast_builder.dart
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| @@ -15,6 +15,8 @@ import 'package:front_end/src/fasta/scanner/token.dart'
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|      show BeginGroupToken, Token;
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|  
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|  import 'package:front_end/src/fasta/errors.dart' show internalError;
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| +import 'package:front_end/src/fasta/fasta_codes.dart'
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| +    show FastaMessage, codeExpectedExpression;
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|  import 'package:front_end/src/fasta/kernel/kernel_builder.dart'
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|      show Builder, KernelLibraryBuilder, ProcedureBuilder;
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|  import 'package:front_end/src/fasta/parser/identifier_context.dart'
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| @@ -30,7 +32,6 @@ import 'element_store.dart'
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|          ElementStore,
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|          KernelClassElement;
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|  import 'package:analyzer/src/dart/error/syntactic_errors.dart';
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| -import 'package:front_end/src/fasta/parser/error_kind.dart';
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|  import 'token_utils.dart' show toAnalyzerToken, toAnalyzerCommentToken;
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|  
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|  class AstBuilder extends ScopeListener {
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| @@ -1046,8 +1047,8 @@ class AstBuilder extends ScopeListener {
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|    }
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|  
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|    @override
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| -  Token handleUnrecoverableError(Token token, ErrorKind kind, Map arguments) {
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| -    if (kind == ErrorKind.ExpectedExpression) {
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| +  Token handleUnrecoverableError(Token token, FastaMessage message) {
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| +    if (message.code == codeExpectedExpression) {
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|        String lexeme = token.lexeme;
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|        if (identical('async', lexeme) || identical('yield', lexeme)) {
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|          errorReporter?.reportErrorForOffset(
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| @@ -1058,7 +1059,7 @@ class AstBuilder extends ScopeListener {
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|          return token;
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|        }
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|      }
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| -    return super.handleUnrecoverableError(token, kind, arguments);
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| +    return super.handleUnrecoverableError(token, message);
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|    }
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|  
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|    void handleUnaryPrefixExpression(Token token) {
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| 
 |