[Sync] Sync client should to exponential backoff when receive partial failure

components/sync/engine_impl/cycle/nudge_tracker.h

 // Copyright 2013 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 COMPONENTS_SYNC_ENGINE_IMPL_CYCLE_NUDGE_TRACKER_H_
 #define COMPONENTS_SYNC_ENGINE_IMPL_CYCLE_NUDGE_TRACKER_H_
 
 #include <stddef.h>
 
 #include <list>
@@ skipping 66 matching lines @@
   // These functions should be called to keep this class informed of the status
   // of the connection to the invalidations server.
   void OnInvalidationsEnabled();
   void OnInvalidationsDisabled();
 
   // Marks |types| as being throttled from |now| until |now| + |length|.
   void SetTypesThrottledUntil(ModelTypeSet types,
                               base::TimeDelta length,
                               base::TimeTicks now);
 
-  // Removes any throttling that have expired by time |now|.
-  void UpdateTypeThrottlingState(base::TimeTicks now);
+  // Marks |type| as being backed off from |now| until |now| + |length|.
+  void SetTypeBackedOff(ModelType type,
+                        base::TimeDelta length,
+                        base::TimeTicks now);
+
+  // Removes any throttling and backoff that have expired by time |now|.
+  void UpdateTypeThrottlingAndBackoffState(base::TimeTicks now);
 
   // Returns the time of the next type unthrottling, relative to
   // the input |now| value.
   base::TimeDelta GetTimeUntilNextUnthrottle(base::TimeTicks now) const;
 
+  // Returns the time of the next type unbackoff, relative to
+  // the input |now| value.
+  base::TimeDelta GetTimeUntilNextUnbackoff(base::TimeTicks now) const;
+
+  // Returns the time of for type last backing off interval.
+  base::TimeDelta GetTypeLastBackoffInterval(ModelType type) const;
+
   // Returns true if any type is currenlty throttled.
   bool IsAnyTypeThrottled() const;
 
+  // Returns true if any type is currenlty backed off.
+  bool IsAnyTypeBackedOff() const;
+
   // Returns true if |type| is currently throttled.
   bool IsTypeThrottled(ModelType type) const;
 
+  // Returns true if |type| is currently backed off.
+  bool IsTypeBackedOff(ModelType type) const;
+
   // Returns the set of currently throttled types.
   ModelTypeSet GetThrottledTypes() const;
 
+  // Returns the set of currently backed off types.
+  ModelTypeSet GetBackedOffTypes() const;
+
   // Returns the set of types with local changes pending.
   ModelTypeSet GetNudgedTypes() const;
 
   // Returns the set of types that have pending invalidations.
   ModelTypeSet GetNotifiedTypes() const;
 
   // Returns the set of types that have pending refresh requests.
   ModelTypeSet GetRefreshRequestedTypes() const;
 
   // Returns the 'source' of the GetUpdate request.
@@ skipping 84 matching lines @@
   base::TimeDelta minimum_local_nudge_delay_;
   base::TimeDelta local_refresh_nudge_delay_;
   base::TimeDelta remote_invalidation_nudge_delay_;
 
   DISALLOW_COPY_AND_ASSIGN(NudgeTracker);
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_ENGINE_IMPL_CYCLE_NUDGE_TRACKER_H_