[Sync] Add histograms for cookie jar state on Sessions commit

sync/internal_api/public/test/fake_sync_manager.h

Index: sync/internal_api/public/test/fake_sync_manager.h
diff --git a/sync/internal_api/public/test/fake_sync_manager.h b/sync/internal_api/public/test/fake_sync_manager.h
index 9d3bd6b4dc703a41fe2c2ed782d2772dd17c83ff..01b537f3f7818bd9eb561848bae4bc6f6990caaf 100644
--- a/sync/internal_api/public/test/fake_sync_manager.h
+++ b/sync/internal_api/public/test/fake_sync_manager.h
@@ -116,7 +116,7 @@ class FakeSyncManager : public SyncManager {
       syncer::TypeDebugInfoObserver* observer) override;
   void RequestEmitDebugInfo() override;
   void ClearServerData(const ClearServerDataCallback& callback) override;
-  void OnCookieJarChanged(bool account_mismatch) override;
+  void OnCookieJarChanged(bool account_mismatch, bool empty_jar) override;
 
  private:
   scoped_refptr<base::SequencedTaskRunner> sync_task_runner_;