Don't show managed UI in demo mode

Bug: 924832
Change-Id: I6e06e81aea864594caf4ae359064032ad8d22f42
Reviewed-on: https://chromium-review.googlesource.com/c/1434075Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Reviewed-by: Michael Wasserman <msw@chromium.org>
Commit-Queue: Nicolas Ouellet-Payeur <nicolaso@chromium.org>
Cr-Commit-Position: refs/heads/master@{#625810}

chrome/browser/ui/managed_ui.cc

@@ -14,6 +14,7 @@
 #include "chrome/common/chrome_features.h"
 
 #if defined(OS_CHROMEOS)
+#include "chrome/browser/chromeos/login/demo_mode/demo_session.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "components/user_manager/user_manager.h"
@@ -25,6 +26,12 @@ bool ShouldDisplayManagedUi(Profile* profile) {
   if (!base::FeatureList::IsEnabled(features::kShowManagedUi))
     return false;
 
+#if defined(OS_CHROMEOS)
+  // Don't show the UI in demo mode.
+  if (chromeos::DemoSession::IsDeviceInDemoMode())
+    return false;
+#endif
+
   // This profile may have policies configured.
   auto* profile_connector =
       policy::ProfilePolicyConnectorFactory::GetForBrowserContext(profile);