Refactor preference syncing.

chrome/browser/sync/glue/session_model_associator.h

Index: chrome/browser/sync/glue/session_model_associator.h
diff --git a/chrome/browser/sync/glue/session_model_associator.h b/chrome/browser/sync/glue/session_model_associator.h
index 28582e0bdb1ab4f6c60ee445c54d22abce52a33d..393de697c7a6b690e578c3ac8e111472799c505d 100644
--- a/chrome/browser/sync/glue/session_model_associator.h
+++ b/chrome/browser/sync/glue/session_model_associator.h
@@ -49,14 +49,13 @@ static const char kSessionsTag[] = "google_chrome_sessions";
 // Contains all logic for associating the Chrome sessions model and
 // the sync sessions model.
 class SessionModelAssociator
-    : public PerDataTypeAssociatorInterface<TabContents, size_t>,
+    : public NewAssociatorInterface,
       public base::NonThreadSafe {
  public:
   // Does not take ownership of sync_service.
   explicit SessionModelAssociator(ProfileSyncService* sync_service);
   SessionModelAssociator(ProfileSyncService* sync_service,
                          bool setup_for_test);
-  virtual ~SessionModelAssociator();
 
   // The has_nodes out parameter is set to true if the sync model has
   // nodes other than the permanent tagged nodes.  The method may
@@ -171,10 +170,6 @@ class SessionModelAssociator
   // Checks that the tab has navigations and is not a new tab.
   // Note: a new tab page with back/forward history is valid.
   static bool IsValidSessionTab(const SessionTab& tab);
-
-  // Returns the syncable model type.
-  static syncable::ModelType model_type() { return syncable::SESSIONS; }
-
  private:
   FRIEND_TEST_ALL_PREFIXES(ProfileSyncServiceSessionTest, WriteSessionToNode);
   FRIEND_TEST_ALL_PREFIXES(ProfileSyncServiceSessionTest,
@@ -186,6 +181,8 @@ class SessionModelAssociator
   FRIEND_TEST_ALL_PREFIXES(SessionModelAssociatorTest, PopulateSessionWindow);
   FRIEND_TEST_ALL_PREFIXES(SessionModelAssociatorTest, PopulateSessionTab);
 
+  virtual ~SessionModelAssociator();
+
   // Keep all the links to local tab data in one place.
   class TabLinks {
    public: