Add closeBraceTokenFor and use it instead of BeginToken.

pkg/front_end/lib/src/fasta/kernel/body_builder.dart

Index: pkg/front_end/lib/src/fasta/kernel/body_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
index 2669e45b1a62274c175b15584adc4f48af9643c2..720ed79084120164a6a5bff99955b66967bcdef7 100644
--- a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@@ -15,8 +15,6 @@ import 'package:kernel/core_types.dart' show CoreTypes;
 
 import 'package:kernel/transformations/flags.dart' show TransformerFlag;
 
-import '../../scanner/token.dart' show BeginToken, Token;
-
 import '../fasta_codes.dart' as fasta;
 
 import '../fasta_codes.dart' show LocatedMessage, Message;
@@ -28,7 +26,13 @@ import '../modifier.dart' show Modifier, constMask, finalMask;
 import '../parser/native_support.dart' show skipNativeClause;
 
 import '../parser.dart'
-    show Assert, FormalParameterKind, IdentifierContext, MemberKind, optional;
+    show
+        Assert,
+        FormalParameterKind,
+        IdentifierContext,
+        MemberKind,
+        closeBraceTokenFor,
+        optional;
 
 import '../parser/formal_parameter_kind.dart'
     show isOptionalPositionalFormalParameterKind;
@@ -45,6 +49,8 @@ import '../quote.dart'
         unescapeLastStringPart,
         unescapeString;
 
+import '../scanner.dart' show Token;
+
 import '../scanner/token.dart' show isBinaryOperator, isMinusOperator;
 
 import '../scope.dart' show ProblemBuilder;
@@ -741,9 +747,10 @@ class BodyBuilder extends ScopeListener<JumpTarget> implements BuilderHelper {
   }
 
   @override
-  void handleParenthesizedExpression(BeginToken token) {
+  void handleParenthesizedExpression(Token token) {
     debugEvent("ParenthesizedExpression");
-    push(new ParenthesizedExpression(this, popForValue(), token.endGroup));
+    push(new ParenthesizedExpression(
+        this, popForValue(), closeBraceTokenFor(token)));
   }
 
   @override