Control the frequency of fileBrowserPrivate.onFileTransfersUpdated events.

chrome/browser/chromeos/gdata/gdata_operation_registry.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_GDATA_GDATA_OPERATION_REGISTRY_H_
 #define CHROME_BROWSER_CHROMEOS_GDATA_GDATA_OPERATION_REGISTRY_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 125 matching lines @@
   bool CancelForFilePath(const FilePath& file_path);
 
   // Obtains the list of currently active operations.
   ProgressStatusList GetProgressStatusList();
 
   // Sets an observer. The registry do NOT own observers; before destruction
   // they need to be removed from the registry.
   void AddObserver(Observer* observer);
   void RemoveObserver(Observer* observer);
 
+  // Disables the notification suppression for testing purpose.
+  void DisableNotificationFrequencyControlForTest();
+
  private:
   // Handlers for notifications from Operations.
   friend class Operation;
   // Notifies that an operation has started. This method passes the ownership of
   // the operation to the registry. A fresh operation ID is returned to *id.
   void OnOperationStart(Operation* operation, OperationID* id);
   void OnOperationProgress(OperationID operation);
   void OnOperationFinish(OperationID operation);
   void OnOperationSuspend(OperationID operation);
   void OnOperationResume(Operation* operation, ProgressStatus* new_status);
   void OnOperationAuthFailed();
 
   bool IsFileTransferOperation(const Operation* operation) const;
 
+  // Controls the frequency of notifications, not to flood the listeners with
+  // too many events.
+  bool ShouldNotifyStatusNow(const ProgressStatusList& list);
+  // Sends notifications to the observers after checking that the frequency is
+  // not too high by ShouldNotifyStatusNow.
+  void NotifyStatusToObservers();
+
   typedef IDMap<Operation, IDMapOwnPointer> OperationIDMap;
   OperationIDMap in_flight_operations_;
   ObserverList<Observer> observer_list_;
+  base::Time last_notification_;
+  bool do_notification_frequency_control_;
 
   DISALLOW_COPY_AND_ASSIGN(GDataOperationRegistry);
 };
 
 }  // namespace gdata
 
 #endif  // CHROME_BROWSER_CHROMEOS_GDATA_GDATA_OPERATION_REGISTRY_H_