Ignore the OnAddFile Status for SSTFileManager (#7826)

Summary:
The returned Status is ignored here as some stress tests are failing, presumably when attempting to add an empty file.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7826

Reviewed By: jay-zhuang

Differential Revision: D25742931

fbshipit-source-id: a1fcd620d9472993a009929306dfc421f93eb43b

db/db_impl/db_impl_compaction_flush.cc

@@ -284,7 +284,10 @@ Status DBImpl::FlushMemTableToOutputFile(
       // Notify sst_file_manager that a new file was added
       std::string file_path = MakeTableFileName(
           cfd->ioptions()->cf_paths[0].path, file_meta.fd.GetNumber());
-      s = sfm->OnAddFile(file_path);
+      // TODO (PR7798).  We should only add the file to the FileManager if it
+      // exists. Otherwise, some tests may fail.  Ignore the error in the
+      // interim.
+      sfm->OnAddFile(file_path).PermitUncheckedError();
       if (sfm->IsMaxAllowedSpaceReached()) {
         Status new_bg_error =
             Status::SpaceLimit("Max allowed space was reached");
@@ -627,7 +630,10 @@ Status DBImpl::AtomicFlushMemTablesToOutputFiles(
       if (sfm) {
         std::string file_path = MakeTableFileName(
             cfds[i]->ioptions()->cf_paths[0].path, file_meta[i].fd.GetNumber());
-        s = sfm->OnAddFile(file_path);
+        // TODO (PR7798).  We should only add the file to the FileManager if it
+        // exists. Otherwise, some tests may fail.  Ignore the error in the
+        // interim.
+        sfm->OnAddFile(file_path).PermitUncheckedError();
         if (sfm->IsMaxAllowedSpaceReached() &&
             error_handler_.GetBGError().ok()) {
           Status new_bg_error =