[Payments] Implement openWindow for service worker based payment handler

third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h

Index: third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h
diff --git a/third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h b/third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h
index dbf6ed60ddf062dde123e9bd4961de008e1f7165..a640e770605d083bca3405f2fa66e7b06c93e73d 100644
--- a/third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h
+++ b/third_party/WebKit/public/web/modules/serviceworker/WebServiceWorkerContextClient.h
@@ -272,8 +272,14 @@ class WebServiceWorkerContextClient {
   // should delete the callbacks after calling either onSuccess or onError.
   // WebServiceWorkerClientInfo and WebServiceWorkerError ownerships are
   // passed to the WebServiceWorkerClientsCallbacks implementation.
-  virtual void OpenWindow(const WebURL&,
-                          std::unique_ptr<WebServiceWorkerClientCallbacks>) = 0;
+  virtual void OpenWindowForClients(
+      const WebURL&,
+      std::unique_ptr<WebServiceWorkerClientCallbacks>) = 0;
+
+  // Similar like OpenWindowForClients above.
+  virtual void OpenWindowForPaymentHandler(

[dcheng, 2017/06/06 21:18:06]

Btw, my point was that we should use a consistent name for this throughout,
including in the Blink public API. Do you mind fixing this in a followup?

+      const WebURL&,
+      std::unique_ptr<WebServiceWorkerClientCallbacks>) = 0;
 
   // A suggestion to cache this metadata in association with this URL.
   virtual void SetCachedMetadata(const WebURL& url,