[Payments] Field trial and flag to abort payment request if no card.

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index b01eed8fae993073c469f64894d12d5e44f39cc3..1d2a555a527ee7ccf49e8ca62601921df22ff7c4 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1091,6 +1091,12 @@ const char kTabManagementExperimentTypeElderberry[] =
 
 // Custom WebAPK server URL for the sake of testing.
 const char kWebApkServerUrl[] = "webapk-server-url";
+
+// Enables the abort of a Payment Request when the user has no credit card.
+const char kEnablePaymentRequestNoCardAbort[] = "enable-no-card-abort";
+
+// Disables the abort of a Payment Request when the user has no credit card.
+const char kDisablePaymentRequestNoCardAbort[] = "disable-no-card-abort";
 #endif  // defined(OS_ANDROID)
 
 #if defined(OS_CHROMEOS)