sync: move invalidation version prefs out of SyncPrefs into InvalidatorStorage.

chrome/browser/sync/sync_prefs.h

Index: chrome/browser/sync/sync_prefs.h
diff --git a/chrome/browser/sync/sync_prefs.h b/chrome/browser/sync/sync_prefs.h
index d2cc6adfb1edf0b49b34ea31d1f93044066682d0..31d1d183605432c6a6d2bd721371eed6190a655c 100644
--- a/chrome/browser/sync/sync_prefs.h
+++ b/chrome/browser/sync/sync_prefs.h
@@ -45,7 +45,6 @@ class SyncPrefObserver {
 //   sync_setup_wizard_unittest.cc
 //   two_client_preferences_sync_test.cc
 class SyncPrefs : public base::SupportsWeakPtr<SyncPrefs>,
-                  public sync_notifier::InvalidationStateTracker,
                   public content::NotificationObserver {
  public:
   // |pref_service| may be NULL (for unit tests), but in that case no
@@ -106,12 +105,6 @@ class SyncPrefs : public base::SupportsWeakPtr<SyncPrefs>,
   void SetSpareBootstrapToken(const std::string& token);
 #endif
 
-  // InvalidationStateTracker implementation.
-  virtual sync_notifier::InvalidationVersionMap
-      GetAllMaxVersions() const OVERRIDE;
-  virtual void SetMaxVersion(syncable::ModelType model_type,
-                             int64 max_version) OVERRIDE;
-
   // Merges the given set of types with the set of acknowledged types.
   void AcknowledgeSyncedTypes(syncable::ModelTypeSet types);