[Sync] Move StartAssociation from NonUIDataTypeController to SharedChangeProcessor.

components/sync/driver/shared_change_processor.h

 // Copyright 2014 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_DRIVER_SHARED_CHANGE_PROCESSOR_H_
 #define COMPONENTS_SYNC_DRIVER_SHARED_CHANGE_PROCESSOR_H_
 
 #include <string>
 
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/single_thread_task_runner.h"
 #include "base/synchronization/lock.h"
 #include "components/sync/api/sync_change_processor.h"
 #include "components/sync/api/sync_data.h"
 #include "components/sync/api/sync_error.h"
 #include "components/sync/api/sync_error_factory.h"
 #include "components/sync/api/sync_merge_result.h"
+#include "components/sync/driver/data_type_controller.h"
 #include "components/sync/engine/model_safe_worker.h"
 
 namespace syncer {
 class DataTypeErrorHandler;
 class SyncableService;
 struct UserShare;
 }  // namespace syncer
 
 namespace sync_driver {
 
@@ skipping 15 matching lines @@
 // waiting for non-UI threads.
 //
 // Note: since we control the work being done while holding the lock, we ensure
 // no I/O or other intensive work is done while blocking the UI thread (all
 // the work is in-memory sync interactions).
 //
 // We use virtual methods so that we can use mock's in testing.
 class SharedChangeProcessor
     : public base::RefCountedThreadSafe<SharedChangeProcessor> {
  public:
+  typedef base::Callback<void(
+      DataTypeController::ConfigureResult start_result,
+      const syncer::SyncMergeResult& local_merge_result,
+      const syncer::SyncMergeResult& syncer_merge_result)>
+      StartDoneCallback;
+
   // Create an uninitialized SharedChangeProcessor.
-  SharedChangeProcessor();
+  explicit SharedChangeProcessor(syncer::ModelType type);
+
+  void StartAssociation(StartDoneCallback start_done,
+                        SyncClient* const sync_client,
+                        syncer::UserShare* user_share,
+                        syncer::DataTypeErrorHandler* error_handler);
 
   // Connect to the Syncer and prepare to handle changes for |type|. Will
   // create and store a new GenericChangeProcessor and return a weak pointer to
   // the syncer::SyncableService associated with |type|.
   // Note: If this SharedChangeProcessor has been disconnected, or the
   // syncer::SyncableService was not alive, will return a null weak pointer.
   virtual base::WeakPtr<syncer::SyncableService> Connect(
       SyncClient* sync_client,
       GenericChangeProcessorFactory* processor_factory,
       syncer::UserShare* user_share,
       syncer::DataTypeErrorHandler* error_handler,
-      syncer::ModelType type,
       const base::WeakPtr<syncer::SyncMergeResult>& merge_result);
 
   // Disconnects from the generic change processor. May be called from any
   // thread. After this, all attempts to interact with the change processor by
   // |local_service_| are dropped and return errors. The syncer will be safe to
   // shut down from the point of view of this datatype.
   // Note: Once disconnected, you cannot reconnect without creating a new
   // SharedChangeProcessor.
   // Returns: true if we were previously succesfully connected, false if we were
   // already disconnected.
@@ skipping 18 matching lines @@
 
   // If a datatype context associated with the current type exists, fills
   // |context| and returns true. Otheriwse, if there has not been a context
   // set, returns false.
   virtual bool GetDataTypeContext(std::string* context) const;
 
   virtual syncer::SyncError CreateAndUploadError(
       const tracked_objects::Location& location,
       const std::string& message);
 
+  // Calls local_service_->StopSyncing() and releases our reference to it.
+  void StopLocalService();
+
   ChangeProcessor* generic_change_processor();
 
  protected:
   friend class base::RefCountedThreadSafe<SharedChangeProcessor>;
   virtual ~SharedChangeProcessor();
 
  private:
+  // Record association time.
+  virtual void RecordAssociationTime(base::TimeDelta time);
+
   // Monitor lock for this object. All methods that interact with the change
   // processor must aquire this lock and check whether we're disconnected or
   // not. Once disconnected, all attempted changes to or loads from the change
   // processor return errors. This enables us to shut down the syncer without
   // having to wait for possibly non-UI thread datatypes to complete work.
   mutable base::Lock monitor_lock_;
   bool disconnected_;
 
-  // The sync datatype we were last connected to.
-  syncer::ModelType type_;
+  // The sync datatype we process changes for.
+  const syncer::ModelType type_;
 
   // The frontend / UI MessageLoop this object is constructed on. May also be
   // destructed and/or disconnected on this loop, see ~SharedChangeProcessor.
   const scoped_refptr<const base::SingleThreadTaskRunner> frontend_task_runner_;
 
   // The loop that all methods except the constructor, destructor, and
   // Disconnect() should be called on.  Set in Connect().
   scoped_refptr<base::SingleThreadTaskRunner> backend_task_runner_;
 
   // Used only on |backend_loop_|.
   GenericChangeProcessor* generic_change_processor_;
 
   syncer::DataTypeErrorHandler* error_handler_;
 
+  // The local service for this type. Only set if the DTC for the type uses
+  // SharedChangeProcessor::StartAssociation().
+  base::WeakPtr<syncer::SyncableService> local_service_;
+
   DISALLOW_COPY_AND_ASSIGN(SharedChangeProcessor);
 };
 
 }  // namespace sync_driver
 
 #endif  // COMPONENTS_SYNC_DRIVER_SHARED_CHANGE_PROCESSOR_H_