Make sure key::kEnableWebBasedSignin policy also turns on command line arg

chrome/browser/policy/chrome_browser_policy_connector.cc

 // Copyright 2014 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 "chrome/browser/policy/chrome_browser_policy_connector.h"
 
 #include <string>
 
 #include "base/callback.h"
 #include "base/command_line.h"
@@ skipping 113 matching lines @@
 }
 
 void ChromeBrowserPolicyConnector::AppendExtraFlagPerPolicy() {
   PolicyService* policy_service = GetPolicyService();
   PolicyNamespace chrome_ns = PolicyNamespace(POLICY_DOMAIN_CHROME, "");
   const PolicyMap& chrome_policy = policy_service->GetPolicies(chrome_ns);
   const base::Value* policy_value =
       chrome_policy.GetValue(key::kEnableWebBasedSignin);
   bool enabled = false;
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
-  if (policy_value && policy_value->GetAsBoolean(&enabled) && enabled &&
-      !command_line->HasSwitch(switches::kEnableWebBasedSignin)) {
-    command_line->AppendSwitch(switches::kEnableWebBasedSignin);
+  if (policy_value && policy_value->GetAsBoolean(&enabled) && enabled) {
+    if (!command_line->HasSwitch(switches::kEnableWebBasedSignin))
+      command_line->AppendSwitch(switches::kEnableWebBasedSignin);
+    // In M41, to fully enable web-based sign in, the kEnableIframeBasedSignin
+    // must also be specified.
+    if (!command_line->HasSwitch(switches::kEnableIframeBasedSignin))
+      command_line->AppendSwitch(switches::kEnableIframeBasedSignin);
   }
 }
 
 }  // namespace policy