[Signin] Add timeout to Dice token exchange requests

chrome/browser/signin/dice_response_handler.h

 // 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_DICE_RESPONSE_HANDLER_H_
 #define CHROME_BROWSER_SIGNIN_DICE_RESPONSE_HANDLER_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
+#include "base/cancelable_callback.h"
 #include "base/macros.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "google_apis/gaia/gaia_auth_consumer.h"
 
 namespace signin {
 struct DiceResponseParams;
 }
 
 class AccountTrackerService;
 class GaiaAuthFetcher;
 class GoogleServiceAuthError;
 class SigninClient;
 class ProfileOAuth2TokenService;
 class Profile;
 
+// Exposed for testing.
+extern const int kDiceTokenFetchTimeoutSeconds;
+
 // Processes the Dice responses from Gaia.
 class DiceResponseHandler : public KeyedService {
  public:
   // Returns the DiceResponseHandler associated with this profile.
   // May return nullptr if there is none (e.g. in incognito).
   static DiceResponseHandler* GetForProfile(Profile* profile);
 
   DiceResponseHandler(SigninClient* signin_client,
                       ProfileOAuth2TokenService* profile_oauth2_token_service,
                       AccountTrackerService* account_tracker_service);
   ~DiceResponseHandler() override;
 
   // Must be called when receiving a Dice response header.
   void ProcessDiceHeader(const signin::DiceResponseParams& dice_params);
 
+  // Returns the number of pending DiceTokenFetchers. Exposed for testing.
+  size_t GetPendingDiceTokenFetchersCountForTesting() const;
+
  private:
   // Helper class to fetch a refresh token from an authorization code.
   class DiceTokenFetcher : public GaiaAuthConsumer {
    public:
     DiceTokenFetcher(const std::string& gaia_id,
                      const std::string& email,
                      const std::string& authorization_code,
                      SigninClient* signin_client,
                      DiceResponseHandler* dice_response_handler);
     ~DiceTokenFetcher() override;
 
     const std::string& gaia_id() const { return gaia_id_; }
     const std::string& email() const { return email_; }
     const std::string& authorization_code() const {
       return authorization_code_;
     }
 
    private:
+    // Called by |timeout_closure_| when the request times out.
+    void OnTimeout();
+
     // GaiaAuthConsumer implementation:
     void OnClientOAuthSuccess(
         const GaiaAuthConsumer::ClientOAuthResult& result) override;
     void OnClientOAuthFailure(const GoogleServiceAuthError& error) override;
 
     std::string gaia_id_;
     std::string email_;
     std::string authorization_code_;
     DiceResponseHandler* dice_response_handler_;
+    base::CancelableClosure timeout_closure_;
     std::unique_ptr<GaiaAuthFetcher> gaia_auth_fetcher_;
 
     DISALLOW_COPY_AND_ASSIGN(DiceTokenFetcher);
   };
 
   // Deletes the token fetcher.
   void DeleteTokenFetcher(DiceTokenFetcher* token_fetcher);
 
   // Process the Dice signin action.
   void ProcessDiceSigninHeader(const std::string& gaia_id,
@@ skipping 12 matching lines @@
 
   SigninClient* signin_client_;
   ProfileOAuth2TokenService* token_service_;
   AccountTrackerService* account_tracker_service_;
   std::vector<std::unique_ptr<DiceTokenFetcher>> token_fetchers_;
 
   DISALLOW_COPY_AND_ASSIGN(DiceResponseHandler);
 };
 
 #endif  // CHROME_BROWSER_SIGNIN_DICE_RESPONSE_HANDLER_H_