fixes #516, nested cascade code generation

lib/src/js_ast/template.dart

Index: lib/src/js_ast/template.dart
diff --git a/lib/src/js_ast/template.dart b/lib/src/js_ast/template.dart
index eb55252a95903d41d2029c076ae9324af6c96e29..7df213d53abf429cc3c646d2c32b114c5bb3984f 100644
--- a/lib/src/js_ast/template.dart
+++ b/lib/src/js_ast/template.dart
@@ -121,15 +121,6 @@ class Template {
     }
     return instantiator(arguments);
   }
-
-  /// Like [instantiate] but works with free variables.
-  Node safeCreate(Map arguments) {
-    if (holeNames.isEmpty) return ast;
-    return instantiator(new Map.fromIterable(holeNames, value: (name) {
-      var a = arguments[name];
-      return a != null ? a : new InterpolatedExpression(name);
-    }));
-  }
 }
 
 /**