Make string juxtaposition combine properly with string interpolations.

frog/leg/scanner/parser.dart

Index: frog/leg/scanner/parser.dart
diff --git a/frog/leg/scanner/parser.dart b/frog/leg/scanner/parser.dart
index 83a2d0d3159d389609599e3f3b2bcbac2d5f21fd..104bb4f5b3e12a7ae48ca59abe05379e39878310 100644
--- a/frog/leg/scanner/parser.dart
+++ b/frog/leg/scanner/parser.dart
@@ -1206,7 +1206,7 @@ class Parser {
       count++;
     }
     if (count > 1) {
-      listener.handleLiteralStringJuxtaposition(count);
+      listener.handleStringJuxtaposition(count);
     }
     return token;
   }