Mark supervised profiles as such immediately when they're created.

chrome/browser/extensions/webstore_startup_installer_browsertest.cc

 // Copyright (c) 2012 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/chrome_notification_types.h"
 #include "chrome/browser/extensions/extension_host.h"
 #include "chrome/browser/extensions/extension_install_ui.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
@@ skipping 153 matching lines @@
   extension_service->AddExtension(hosted_app.get());
   EXPECT_TRUE(extension_service->extensions()->Contains(hosted_app->id()));
 
   ui_test_utils::NavigateToURL(browser(), kInstallUrl);
 
   EXPECT_FALSE(extension_service->extensions()->Contains(kTestExtensionId));
   RunTest("runTest");
   EXPECT_TRUE(extension_service->extensions()->Contains(kTestExtensionId));
 }
 
-IN_PROC_BROWSER_TEST_F(WebstoreStartupInstallerTest,
-                       InstallProhibitedForManagedUsers) {
+class WebstoreStartupInstallerManagedUsersTest
+    : public WebstoreStartupInstallerTest {
+ public:
+  // InProcessBrowserTest overrides:
+  virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
+    WebstoreStartupInstallerTest::SetUpCommandLine(command_line);
+    command_line->AppendSwitch(switches::kNewProfileIsSupervised);
+  }
+};
+
+IN_PROC_BROWSER_TEST_F(WebstoreStartupInstallerManagedUsersTest,
+                       InstallProhibited) {
 #if defined(OS_WIN) && defined(USE_ASH)
   // Disable this test in Metro+Ash for now (http://crbug.com/262796).
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kAshBrowserTests))
     return;
 #endif
 
   CommandLine::ForCurrentProcess()->AppendSwitchASCII(
       switches::kAppsGalleryInstallAutoConfirmForTests, "accept");
 
-  // Make the profile managed such that no extension installs are allowed.
-  ManagedUserService* service =
-      ManagedUserServiceFactory::GetForProfile(browser()->profile());
-  service->InitForTesting();
-
   ui_test_utils::NavigateToURL(
       browser(), GenerateTestServerUrl(kAppDomain, "install_prohibited.html"));
 
   RunTest("runTest");
 
   // No error infobar should show up.
   WebContents* contents = browser()->tab_strip_model()->GetActiveWebContents();
   InfoBarService* info_bar_service = InfoBarService::FromWebContents(contents);
   EXPECT_EQ(info_bar_service->infobar_count(), 0u);
 }
@@ skipping 119 matching lines @@
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   command_line->AppendSwitchASCII(
       switches::kLimitedInstallFromWebstore, "2");
   helper.LimitedInstallFromWebstore(*command_line, browser()->profile(),
       base::MessageLoop::QuitWhenIdleClosure());
   base::MessageLoop::current()->Run();
 
   EXPECT_TRUE(saw_install());
   EXPECT_EQ(0, browser_open_count());
 }