[Sync] Add cookie jar mismatch logging

components/sync_driver/glue/sync_backend_host.h

Index: components/sync_driver/glue/sync_backend_host.h
diff --git a/components/sync_driver/glue/sync_backend_host.h b/components/sync_driver/glue/sync_backend_host.h
index 081c31533911d60cb9bf3b7a06cf767bacf84401..dc9962e96585e1c8fd341216290b36e8a79b5760 100644
--- a/components/sync_driver/glue/sync_backend_host.h
+++ b/components/sync_driver/glue/sync_backend_host.h
@@ -227,6 +227,10 @@ class SyncBackendHost : public sync_driver::BackendDataTypeConfigurer {
   virtual void ClearServerData(
       const syncer::SyncManager::ClearServerDataCallback& callback) = 0;
 
+  // Notify the syncer that the cookie jar has changed.
+  // See SyncManager::OnCookieJarChanged.
+  virtual void OnCookieJarChanged(bool account_mismatch) = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(SyncBackendHost);
 };