[Payments] Put Web Payments feature on desktop behind flag

chrome/browser/payments/site_per_process_payments_browsertest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/web_contents.h"
+#include "content/public/common/content_features.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/test_utils.h"
 #include "net/dns/mock_host_resolver.h"
 #include "net/test/embedded_test_server/embedded_test_server.h"
 #include "url/gurl.h"
 #include "url/url_constants.h"
 
 namespace payments {
 
 class SitePerProcessPaymentsBrowserTest : public InProcessBrowserTest {
  public:
   SitePerProcessPaymentsBrowserTest() {}
   ~SitePerProcessPaymentsBrowserTest() override {}
 
   void SetUpCommandLine(base::CommandLine* command_line) override {
     InProcessBrowserTest::SetUpCommandLine(command_line);
     // HTTPS server only serves a valid cert for localhost, so this is needed
     // to load pages from other hosts without an error.
     command_line->AppendSwitch(switches::kIgnoreCertificateErrors);
     command_line->AppendSwitch(
         switches::kEnableExperimentalWebPlatformFeatures);
+    command_line->AppendSwitchASCII(switches::kEnableFeatures,
+                                    features::kWebPayments.name);
     // Append --site-per-process flag.
     content::IsolateAllSitesForTesting(command_line);
   }
 
   void SetUpOnMainThread() override {
     https_server_.reset(
         new net::EmbeddedTestServer(net::EmbeddedTestServer::TYPE_HTTPS));
     host_resolver()->AddRule("*", "127.0.0.1");
     ASSERT_TRUE(https_server_->InitializeAndListen());
     content::SetupCrossSiteRedirector(https_server_.get());
@@ skipping 18 matching lines @@
       https_server_->GetURL("b.com", "/payment_request_iframe.html");
   EXPECT_TRUE(content::NavigateIframeToURL(tab, "test", iframe_url));
 
   EXPECT_TRUE(tab->GetRenderWidgetHostView()->IsShowing());
   content::RenderFrameHost* frame = ChildFrameAt(tab->GetMainFrame(), 0);
   EXPECT_TRUE(frame);
   EXPECT_NE(frame->GetSiteInstance(), tab->GetMainFrame()->GetSiteInstance());
 }
 
 }  // namespace payments