PaymentApp: Add classes for supporting Web Based Payment Apps

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 6d8a898fdc971bf7be056cb377e93bb0c9e7c5c2..7f5ff9ffdfa861ccf8404350db93a170dd1abd33 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -445,6 +445,11 @@ const char kEnableQuicPortSelection[] = "enable-quic-port-selection";
 // Switches 'Save as...' context and app menu labels to 'Download...'.
 const char kEnableSaveAsMenuLabelExperiment[] = "saveas-menu-label";
 
+// Enable support for service-worker based payment apps as defined by w3c here:
+// https://w3c.github.io/webpayments-payment-apps-api/
+const char kEnableServiceWorkerPaymentApps[] =
+    "enable-service-worker-payment-apps";
+
 // Enable settings in a separate browser window per profile
 // (see SettingsWindowEnabled() below).
 const char kEnableSettingsWindow[]           = "enable-settings-window";