[Merge M-56] Gate web payments iframe support on runtime enabled feature.

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

Index: third_party/WebKit/Source/modules/payments/PaymentRequest.cpp
diff --git a/third_party/WebKit/Source/modules/payments/PaymentRequest.cpp b/third_party/WebKit/Source/modules/payments/PaymentRequest.cpp
index 13ec5ffd3672c0c2e3d0db43bb942134d45277e2..9712568e30b23b5423fb567e91dc428664fe23a3 100644
--- a/third_party/WebKit/Source/modules/payments/PaymentRequest.cpp
+++ b/third_party/WebKit/Source/modules/payments/PaymentRequest.cpp
@@ -524,8 +524,10 @@ bool allowedToUsePaymentRequest(const Frame* frame) {
   // is an iframe element with an |allowpaymentrequest| attribute specified, and
   // whose node document is allowed to use the feature indicated by
   // |allowpaymentrequest|, then return true.
-  if (frame->owner() && frame->owner()->allowPaymentRequest())
+  if (RuntimeEnabledFeatures::paymentRequestIFrameEnabled() && frame->owner() &&
+      frame->owner()->allowPaymentRequest()) {
     return allowedToUsePaymentRequest(frame->tree().parent());
+  }
 
   // 4. Return false.
   return false;