dart2js: fix typo

pkg/compiler/lib/src/compile_time_constants.dart

Index: pkg/compiler/lib/src/compile_time_constants.dart
diff --git a/pkg/compiler/lib/src/compile_time_constants.dart b/pkg/compiler/lib/src/compile_time_constants.dart
index f5ec1ee877f9109ef3a0c0cff7af4aa6d5ac6f84..b203ec131a418f4730880d49caad317eeb36af95 100644
--- a/pkg/compiler/lib/src/compile_time_constants.dart
+++ b/pkg/compiler/lib/src/compile_time_constants.dart
@@ -336,7 +336,7 @@ class CompileTimeConstantEvaluator extends Visitor<AstConstant> {
   ConstantSystem get constantSystem => handler.constantSystem;
 
   AstConstant evaluate(Node node) {
-    // TODO(johnniwinter): should there be a visitErrorNode?
+    // TODO(johnniwinther): should there be a visitErrorNode?
     if (node is ErrorNode) return new ErroneousAstConstant(context, node);
     return node.accept(this);
   }