sync: Refactor job ownership in SyncScheduler

sync/engine/sync_session_job.h

 // Copyright 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 SYNC_ENGINE_SYNC_SESSION_JOB_H_
 #define SYNC_ENGINE_SYNC_SESSION_JOB_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time.h"
@@ skipping 19 matching lines @@
     // during initial sync or reconfiguration.
     CONFIGURATION,
   };
 
   SyncSessionJob(Purpose purpose,
                  base::TimeTicks start,
                  const sessions::SyncSourceInfo& source_info,
                  const ConfigurationParams& config_params);
   ~SyncSessionJob();
 
-  // Returns a new clone of the job, with a cloned SyncSession ready to be
-  // retried / rescheduled.
-  scoped_ptr<SyncSessionJob> Clone() const;
-
   // Overwrite the sync update source with the most recent and merge the
   // type/state map.
   void CoalesceSources(const sessions::SyncSourceInfo& source);
 
   // Record that the scheduler has deemed the job as finished and give it a
   // chance to perform any remaining cleanup and/or notification completion
   // callback invocations.
   // |early_exit| specifies whether the job 1) cycled through all the
   // SyncerSteps it needed, or 2) was pre-empted by the scheduler.
   // Returns true if we completely ran the session without errors.
@@ skipping 14 matching lines @@
 
   Purpose purpose() const;
   const sessions::SyncSourceInfo& source_info() const;
   base::TimeTicks scheduled_start() const;
   void set_scheduled_start(base::TimeTicks start);
   SyncerStep start_step() const;
   SyncerStep end_step() const;
   ConfigurationParams config_params() const;
 
  private:
-  // A SyncSessionJob can be in one of these three states, controlled by the
-  // Finish() function, see method comments.
-  enum FinishedState {
-    NOT_FINISHED,  // Finish has not been called.
-    EARLY_EXIT,    // Finish was called but the job was "preempted",
-    FINISHED       // Indicates a "clean" finish operation.
-  };
-
   const Purpose purpose_;
   sessions::SyncSourceInfo source_info_;
 
   base::TimeTicks scheduled_start_;
 
   // Only used for purpose_ == CONFIGURATION.  This, and different Finish() and
   // Succeeded() behavior may be arguments to subclass in the future.
   const ConfigurationParams config_params_;
 
-  // Set to true if Finish() was called, false otherwise. True implies that
-  // a SyncShare operation took place with |session_| and it cycled through
-  // all requisite steps given |purpose_| without being preempted.
-  FinishedState finished_;
-
   DISALLOW_COPY_AND_ASSIGN(SyncSessionJob);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_ENGINE_SYNC_SESSION_JOB_H_