Fix for parsing 'rethrow' statement with Fasta.

pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart

Index: pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart b/pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart
index 1328100c04bec731b049664377213bf165df956f..c8d18058cb7747c922e735e4b9ec35c704bc4d92 100644
--- a/pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart
+++ b/pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart
@@ -566,6 +566,15 @@ class AstBuilder extends ScopeListener {
         thenExpression, toAnalyzerToken(colon), elseExpression));
   }
 
+  @override
+  void endRethrowStatement(Token throwToken, Token endToken) {

[Brian Wilkerson, 2017/03/06 19:47:28]

"throwToken" --> "rethrowToken"?

+    debugEvent("RethrowStatement");
+    RethrowExpression expression =
+        ast.rethrowExpression(toAnalyzerToken(throwToken));
+    // TODO(scheglov) According to the specification, 'rethrow' is a statement.
+    push(ast.expressionStatement(expression, toAnalyzerToken(endToken)));
+  }
+
   void endThrowExpression(Token throwToken, Token endToken) {
     debugEvent("ThrowExpression");
     push(ast.throwExpression(toAnalyzerToken(throwToken), pop()));