Force read existing data during db repair (#5209)

Summary:
Setting read_opts.total_order_seek achieves this, even with a different prefix
extractor.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5209

Differential Revision: D14980388

Pulled By: riversand963

fbshipit-source-id: 16527989a3d6b3e3ae8241c894d011326429d66e

db/repair.cc

@@ -517,8 +517,10 @@ class Repairer {
       }
     }
     if (status.ok()) {
+      ReadOptions ropts;
+      ropts.total_order_seek = true;
       InternalIterator* iter = table_cache_->NewIterator(
-          ReadOptions(), env_options_, cfd->internal_comparator(), t->meta,
+          ropts, env_options_, cfd->internal_comparator(), t->meta,
           nullptr /* range_del_agg */,
           cfd->GetLatestMutableCFOptions()->prefix_extractor.get());
       bool empty = true;