Throw if PaymentRequest() built with 'error' message

third_party/WebKit/Source/modules/payments/PaymentTestHelper.cpp

Index: third_party/WebKit/Source/modules/payments/PaymentTestHelper.cpp
diff --git a/third_party/WebKit/Source/modules/payments/PaymentTestHelper.cpp b/third_party/WebKit/Source/modules/payments/PaymentTestHelper.cpp
index e9d25f51cc14e5113de6a172f69255e19d28a5e1..8f7d76a535b6970e0282ed072f3e68ca77bd1f83 100644
--- a/third_party/WebKit/Source/modules/payments/PaymentTestHelper.cpp
+++ b/third_party/WebKit/Source/modules/payments/PaymentTestHelper.cpp
@@ -138,17 +138,15 @@ PaymentDetails buildPaymentDetailsForTest(
   else
     modifier = buildPaymentDetailsModifierForTest();
 
-  String errorMessage = "";
-  if (detail == PaymentTestDetailError)
-    errorMessage = valueToUse;
-
   PaymentDetails result;
   result.setTotal(total);
   result.setDisplayItems(HeapVector<PaymentItem>(1, item));
   result.setShippingOptions(
       HeapVector<PaymentShippingOption>(1, shippingOption));
   result.setModifiers(HeapVector<PaymentDetailsModifier>(1, modifier));
-  result.setError(errorMessage);
+
+  if (detail == PaymentTestDetailError)
+    result.setError(valueToUse);
 
   return result;
 }