Fix scanning of change delimiter tags
diff --git a/lib/src/scanner2.dart b/lib/src/scanner2.dart
index 2900c5b..5eac510 100644
--- a/lib/src/scanner2.dart
+++ b/lib/src/scanner2.dart
@@ -275,6 +275,8 @@
   // Open delimiter characters and = have already been read.
   void _scanChangeDelimiterTag(int start) {
     
+    _expect(_EQUAL);
+    
     var delimiterInner = _closeDelimiterInner;
     var delimiter = _closeDelimiter;