Fix build break introduced by new SyncPoint interface change

Summary: When commiting the sync point interface change, didn't resolve the new occurance of the old interface in rebase. Fix it.

Test Plan: Build and see it pass

Reviewers: igor, yhchiang, rven, anthony, kradhakrishnan

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D37095

db/db_test.cc

@@ -11109,7 +11109,8 @@ TEST_F(DBTest, DynamicLevelMaxBytesBaseInc) {
 
   int non_trivial = 0;
   rocksdb::SyncPoint::GetInstance()->SetCallBack(
-      "DBImpl::BackgroundCompaction:NonTrivial", [&]() { non_trivial++; });
+      "DBImpl::BackgroundCompaction:NonTrivial",
+      [&](void* arg) { non_trivial++; });
   rocksdb::SyncPoint::GetInstance()->EnableProcessing();
 
   Random rnd(301);