Revert 148792 - [Sync] Remove CleanupDisabledTypes command and move purge logic into SyncManager.

sync/sessions/sync_session_context.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.
 
 // SyncSessionContext encapsulates the contextual information and engine
 // components specific to a SyncSession. A context is accessible via
 // a SyncSession so that session SyncerCommands and parts of the engine have
 // a convenient way to access other parts. In this way it can be thought of as
 // the surrounding environment for the SyncSession. The components of this
 // environment are either valid or not valid for the entire context lifetime,
@@ skipping 92 matching lines @@
     DCHECK(account_name_.empty());
     account_name_ = name;
   }
   const std::string& account_name() const { return account_name_; }
 
   void set_max_commit_batch_size(int batch_size) {
     max_commit_batch_size_ = batch_size;
   }
   int32 max_commit_batch_size() const { return max_commit_batch_size_; }
 
+  const ModelSafeRoutingInfo& previous_session_routing_info() const {
+    return previous_session_routing_info_;
+  }
+
+  void set_previous_session_routing_info(const ModelSafeRoutingInfo& info) {
+    previous_session_routing_info_ = info;
+  }
+
   void NotifyListeners(const SyncEngineEvent& event) {
     FOR_EACH_OBSERVER(SyncEngineEventListener, listeners_,
                       OnSyncEngineEvent(event));
   }
 
   TrafficRecorder* traffic_recorder() {
     return traffic_recorder_;
   }
 
  private:
@@ skipping 25 matching lines @@
   // Kept up to date with talk events to determine whether notifications are
   // enabled. True only if the notification channel is authorized and open.
   bool notifications_enabled_;
 
   // The name of the account being synced.
   std::string account_name_;
 
   // The server limits the number of items a client can commit in one batch.
   int max_commit_batch_size_;
 
+  // Some routing info history to help us clean up types that get disabled
+  // by the user.
+  ModelSafeRoutingInfo previous_session_routing_info_;
+
   ThrottledDataTypeTracker* throttled_data_type_tracker_;
 
   // We use this to get debug info to send to the server for debugging
   // client behavior on server side.
   DebugInfoGetter* const debug_info_getter_;
 
   TrafficRecorder* traffic_recorder_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncSessionContext);
 };
@@ skipping 18 matching lines @@
  private:
   SyncSessionContext* context_;
   ConflictResolver* resolver_;
   DISALLOW_COPY_AND_ASSIGN(ScopedSessionContextConflictResolver);
 };
 
 }  // namespace sessions
 }  // namespace syncer
 
 #endif  // SYNC_SESSIONS_SYNC_SESSION_CONTEXT_H_