Add ForceSigninVerifier.

chrome/browser/signin/force_signin_verifier.h

Index: chrome/browser/signin/force_signin_verifier.h
diff --git a/chrome/browser/signin/force_signin_verifier.h b/chrome/browser/signin/force_signin_verifier.h
new file mode 100644
index 0000000000000000000000000000000000000000..03548c03eba884fdc7343e9671601586617852a0
--- /dev/null
+++ b/chrome/browser/signin/force_signin_verifier.h
@@ -0,0 +1,84 @@
+// Copyright 2017 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_SIGNIN_FORCE_SIGNIN_VERIFIER_H_
+#define CHROME_BROWSER_SIGNIN_FORCE_SIGNIN_VERIFIER_H_
+
+#include <memory>
+#include <string>
+
+#include "base/macros.h"
+#include "base/time/time.h"
+#include "base/timer/timer.h"
+#include "google_apis/gaia/oauth2_token_service.h"
+#include "net/base/backoff_entry.h"
+#include "net/base/network_change_notifier.h"
+
+class Profile;
+class SigninManager;
+
+// ForceSigninVerifier will verify profile's auth token when profile is loaded
+// into memory by the first time via gaia server. It will retry on any transient
+// error.
+class ForceSigninVerifier
+    : public OAuth2TokenService::Consumer,
+      public net::NetworkChangeNotifier::NetworkChangeObserver {
+ public:
+  explicit ForceSigninVerifier(Profile* profile);
+  ~ForceSigninVerifier() override;
+
+  // OAuth2TokenService::Consumer implementation
+  void OnGetTokenSuccess(const OAuth2TokenService::Request* request,
+                         const std::string& access_token,
+                         const base::Time& expiration_time) override;
+  void OnGetTokenFailure(const OAuth2TokenService::Request* request,
+                         const GoogleServiceAuthError& error) override;
+
+  // net::NetworkChangeNotifier::NetworkChangeObserver
+  void OnNetworkChanged(
+      net::NetworkChangeNotifier::ConnectionType type) override;
+
+  // Cancel any pending or ongoing verification.
+  void Cancel();
+
+  // Return the value of |has_token_verified_|.
+  bool HasTokenBeenVerified();
+
+ protected:
+  // Send the token verification request. The request will be sent only if
+  //   - The token has never been verified before.
+  //   - There is no on going verification.
+  //   - There is network connection.
+  //   - The profile has signed in.
+  //
+  void SendRequest();
+
+  virtual bool ShouldSendRequest();
+
+  // Show the warning dialog before signing out user and closing assoicated
+  // browser window.
+  virtual void ShowDialog();
+
+  OAuth2TokenService::Request* GetRequestForTesting();
+  net::BackoffEntry* GetBackoffEntryForTesting();
+  base::OneShotTimer* GetOneShotTimerForTesting();
+
+ private:
+  std::unique_ptr<OAuth2TokenService::Request> access_token_request_;
+
+  // Indicates whether the verification is finished successfully or with a
+  // persistent error.
+  bool has_token_verified_;
+  net::BackoffEntry backoff_entry_;
+  base::OneShotTimer backoff_request_timer_;
+
+  OAuth2TokenService* oauth2_token_service_;
+  SigninManager* signin_manager_;
+
+  base::Time token_request_time_;
+
+  DISALLOW_COPY_AND_ASSIGN(ForceSigninVerifier);
+};
+
+#endif  // CHROME_BROWSER_SIGNIN_FORCE_SIGNIN_VERIFIER_H_