Decode response ABI only if there supposed to be return values

assets/js/universal-dapp.js

@@ -352,6 +352,8 @@ UniversalDApp.prototype.getCallButton = function(args) {
                 clearOutput($result);
                 $result.append(getReturnOutput(outputObj)).append(getGasUsedOutput(result.vm));
 
+                // Only decode if there supposed to be fields
+                if (args.abi.outputs.length > 0) {
                     try {
                         var outputTypes = [];
                         for (var i = 0; i < args.abi.outputs.length; i++) {
@@ -370,6 +372,7 @@ UniversalDApp.prototype.getCallButton = function(args) {
                         $result.append(getDecodedOutput(decodedObj));
                     } catch (e) {
                     }
+                }
             } else if (args.abi.constant && !isConstructor) {
                 replaceOutput($result, getReturnOutput(result));
             } else {