sync: Implement per-type update processing

sync/sessions/sync_session_context.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.
 
 // 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,
 // or they are valid for explicitly scoped periods of time by using Scoped
 // installation utilities found below. This means that the context assumes no
 // ownership whatsoever of any object that was not created by the context
 // itself.
 //
 // It can only be used from the SyncerThread.
 
 #ifndef SYNC_SESSIONS_SYNC_SESSION_CONTEXT_H_
 #define SYNC_SESSIONS_SYNC_SESSION_CONTEXT_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/stl_util.h"
 #include "sync/base/sync_export.h"
 #include "sync/engine/sync_directory_commit_contributor.h"
+#include "sync/engine/sync_directory_update_handler.h"
 #include "sync/engine/sync_engine_event.h"
 #include "sync/engine/syncer_types.h"
 #include "sync/engine/traffic_recorder.h"
 #include "sync/internal_api/public/engine/model_safe_worker.h"
 #include "sync/protocol/sync.pb.h"
 #include "sync/sessions/debug_info_getter.h"
 
 namespace syncer {
 
 class ExtensionsActivity;
@@ skipping 30 matching lines @@
   syncable::Directory* directory() {
     return directory_;
   }
 
   const ModelSafeRoutingInfo& routing_info() const {
     return routing_info_;
   }
 
   void set_routing_info(const ModelSafeRoutingInfo& routing_info);
 
+  UpdateHandlerMap* update_handler_map() {
+    return &update_handler_map_;
+  }
+
   CommitContributorMap* commit_contributor_map() {
     return &commit_contributor_map_;
   }
 
   const std::vector<scoped_refptr<ModelSafeWorker> >& workers() const {
     return workers_;
   }
 
   ExtensionsActivity* extensions_activity() {
     return extensions_activity_.get();
@@ skipping 66 matching lines @@
   ServerConnectionManager* const connection_manager_;
   syncable::Directory* const directory_;
 
   // A cached copy of SyncBackendRegistrar's routing info.
   // Must be updated manually when SBR's state is modified.
   ModelSafeRoutingInfo routing_info_;
 
   // A map of 'commit contributors', one for each enabled type.
   // This must be kept in sync with the routing info.  Our temporary solution to
   // that problem is to initialize this map in set_routing_info().
+  UpdateHandlerMap update_handler_map_;
+
+  // Deleter for the |commit_contributor_map_|.
+  STLValueDeleter<UpdateHandlerMap> update_handler_deleter_;
+
+  // A map of 'commit contributors', one for each enabled type.
+  // This must be kept in sync with the routing info.  Our temporary solution to
+  // that problem is to initialize this map in set_routing_info().
   CommitContributorMap commit_contributor_map_;
 
   // Deleter for the |commit_contributor_map_|.
   STLValueDeleter<CommitContributorMap> commit_contributor_deleter_;
 
   // The set of ModelSafeWorkers.  Used to execute tasks of various threads.
   std::vector<scoped_refptr<ModelSafeWorker> > workers_;
 
   // We use this to stuff extensions activity into CommitMessages so the server
   // can correlate commit traffic with extension-related bookmark mutations.
@@ skipping 38 matching lines @@
   // enable the pre-commit update avoidance experiment described above.
   const bool client_enabled_pre_commit_update_avoidance_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncSessionContext);
 };
 
 }  // namespace sessions
 }  // namespace syncer
 
 #endif  // SYNC_SESSIONS_SYNC_SESSION_CONTEXT_H_