Reauthenticate the user before launching Smart Lock setup app.

chrome/browser/chromeos/login/easy_unlock/short_lived_user_context.h

Index: chrome/browser/chromeos/login/easy_unlock/short_lived_user_context.h
diff --git a/chrome/browser/chromeos/login/easy_unlock/short_lived_user_context.h b/chrome/browser/chromeos/login/easy_unlock/short_lived_user_context.h
new file mode 100644
index 0000000000000000000000000000000000000000..7e4bdabce81d4915cdc6a6ed199870f03d2692fe
--- /dev/null
+++ b/chrome/browser/chromeos/login/easy_unlock/short_lived_user_context.h
@@ -0,0 +1,53 @@
+// 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.
+
+#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_EASY_UNLOCK_SHORT_LIVED_USER_CONTEXT_H_
+#define CHROME_BROWSER_CHROMEOS_LOGIN_EASY_UNLOCK_SHORT_LIVED_USER_CONTEXT_H_
+
+#include "apps/app_lifetime_monitor.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+
+namespace base {
+class TaskRunner;
+}
+
+namespace chromeos {
+
+class UserContext;
+
+// Stores the UserContext of an authentication operation on the sign-in/lock
+// screen, which is used to generate the keys for Easy Sign-in.
+// The lifetime of the user context is bound the the setup app window. As a
+// fail-safe, the user context will also be deleted after a set period of time
+// in case the app is left open indefintely.
+class ShortLivedUserContext : public apps::AppLifetimeMonitor::Observer {
+ public:
+  ShortLivedUserContext(const UserContext& user_context,
+                        apps::AppLifetimeMonitor* app_lifetime_monitor,
+                        base::TaskRunner* task_runner);
+  virtual ~ShortLivedUserContext();
+
+  // The UserContext returned here can be NULL if its time-to-live has expired.
+  UserContext* user_context() { return user_context_.get(); }
+
+ private:
+  void Reset();
+
+  // apps::AppLifetimeMonitor::Observer:
+  virtual void OnAppDeactivated(Profile* profile,
+                                const std::string& app_id) override;
+
+  scoped_ptr<UserContext> user_context_;
+
+  apps::AppLifetimeMonitor* app_lifetime_monitor_;
+
+  base::WeakPtrFactory<ShortLivedUserContext> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(ShortLivedUserContext);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_EASY_UNLOCK_SHORT_LIVED_USER_CONTEXT_H_