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pkg/compiler/lib/src/js_backend/constant_emitter.dart

Index: pkg/compiler/lib/src/js_backend/constant_emitter.dart
diff --git a/pkg/compiler/lib/src/js_backend/constant_emitter.dart b/pkg/compiler/lib/src/js_backend/constant_emitter.dart
index fc53cb4158aece420c3232b6661dbebe9d90fc77..e88d927fdb8f4c819941282cc2f2106576f21723 100644
--- a/pkg/compiler/lib/src/js_backend/constant_emitter.dart
+++ b/pkg/compiler/lib/src/js_backend/constant_emitter.dart
@@ -64,6 +64,11 @@ class ConstantEmitter implements ConstantValueVisitor<jsAst.Expression, Null> {
     return new jsAst.LiteralNull();
   }
 
+  @override
+  jsAst.Expression visitNonConstant(NonConstantValue constant, [_]) {
+    return new jsAst.LiteralNull();
+  }
+
   static final _exponentialRE = new RegExp('^'
       '\([-+]?\)' // 1: sign
       '\([0-9]+\)' // 2: leading digit(s)