[PaymentReqeust] Add error message in PaymentDetails. (in blink side)

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 0455d16b71d46c39345a9ab21ce9d9266eb0dd2a..d7a216813b5f97ae7eae0d9db9b10a6591f10eca 100644
--- a/third_party/WebKit/Source/modules/payments/PaymentTestHelper.cpp
+++ b/third_party/WebKit/Source/modules/payments/PaymentTestHelper.cpp
@@ -114,15 +114,25 @@ PaymentDetails buildPaymentDetailsForTest(PaymentTestDetailToChange detail, Paym
     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);
 
     return result;
 }
 
+PaymentDetails buildPaymentDetailsErrorMsgForTest(const String& valueToUse)
+{
+    return buildPaymentDetailsForTest(PaymentTestDetailError, PaymentTestDataNone, PaymentTestOverwriteValue, valueToUse);
+}
+
 HeapVector<PaymentMethodData> buildPaymentMethodDataForTest()
 {
     HeapVector<PaymentMethodData> methodData(1, PaymentMethodData());