Mark IFrame support in PaymentRequest experimental

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 f67b63bede62e3795377d09323f5ff31669c1382..d9574b234199e19331c949713d7bcecaa0269e9c 100644
--- a/third_party/WebKit/Source/modules/payments/PaymentRequest.cpp
+++ b/third_party/WebKit/Source/modules/payments/PaymentRequest.cpp
@@ -29,6 +29,7 @@
 #include "modules/payments/PaymentsValidators.h"
 #include "mojo/public/cpp/bindings/interface_request.h"
 #include "mojo/public/cpp/bindings/wtf_array.h"
+#include "platform/RuntimeEnabledFeatures.h"
 #include "platform/mojo/MojoHelper.h"
 #include "public/platform/InterfaceProvider.h"
 #include "public/platform/Platform.h"
@@ -519,6 +520,9 @@ bool allowedToUsePaymentRequest(const Frame* frame) {
   if (frame->isMainFrame())
     return true;
 
+  if (!RuntimeEnabledFeatures::paymentRequestIFrameEnabled())

[Rick Byers, 2016/11/23 16:54:55]

nit: this check is now redundant with the check in allowPaymentRequest(), right?
 Maybe remove it or replace by a CHECK somewhere?

[please use gerrit instead, 2016/11/23 17:27:36]

Removed.

+    return false;
+
   // 3. If |document|'s browsing context has a browsing context container that
   // is an iframe element with an |allowpaymentrequest| attribute specified, and
   // whose node document is allowed to use the feature indicated by
@@ -732,8 +736,10 @@ PaymentRequest::PaymentRequest(ScriptState* scriptState,
 
   if (!allowedToUsePaymentRequest(scriptState->domWindow()->frame())) {
     exceptionState.throwSecurityError(
-        "Must be in a top-level browsing context or an iframe needs to specify "
-        "'allowpaymentrequest' explicitly");
+        RuntimeEnabledFeatures::paymentRequestIFrameEnabled()
+            ? "Must be in a top-level browsing context or an iframe needs to "
+              "specify 'allowpaymentrequest' explicitly"
+            : "Must be in a top-level browsing context");
     return;
   }