Parse assert statements with Fasta.

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 b403485cf958f7ff926a4da6fb66f1e08f8fcba9..07de3ab11d36691c08874b867974d1f2f9aeb889 100644
--- a/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/body_builder.dart
@@ -2022,8 +2022,8 @@ class BodyBuilder extends ScopeListener<JumpTarget> implements BuilderHelper {
   }
 
   @override
-  void handleAssertStatement(
-      Token assertKeyword, Token commaToken, Token semicolonToken) {
+  void handleAssertStatement(Token assertKeyword, Token leftParenthesis,
+      Token commaToken, Token rightParenthesis, Token semicolonToken) {
     debugEvent("AssertStatement");
     Expression message = popForValueIfNotNull(commaToken);
     Expression condition = popForValue();