Rename vars to satisfy unity built

Summary:
Tested by "make unity_test"
Closes https://github.com/facebook/rocksdb/pull/3807

Differential Revision: D7882657

Pulled By: maysamyabandeh

fbshipit-source-id: 84862c18d7f2fc762bd96ad070eaeb6936e45159

db/internal_stats.cc

@@ -230,8 +230,8 @@ static const std::string num_live_versions = "num-live-versions";
 static const std::string current_version_number =
     "current-super-version-number";
 static const std::string estimate_live_data_size = "estimate-live-data-size";
-static const std::string min_log_number_to_keep = "min-log-number-to-keep";
-static const std::string base_level = "base-level";
+static const std::string min_log_number_to_keep_str = "min-log-number-to-keep";
+static const std::string base_level_str = "base-level";
 static const std::string total_sst_files_size = "total-sst-files-size";
 static const std::string live_sst_files_size = "live-sst-files-size";
 static const std::string estimate_pending_comp_bytes =
@@ -308,12 +308,12 @@ const std::string DB::Properties::kCurrentSuperVersionNumber =
 const std::string DB::Properties::kEstimateLiveDataSize =
     rocksdb_prefix + estimate_live_data_size;
 const std::string DB::Properties::kMinLogNumberToKeep =
-    rocksdb_prefix + min_log_number_to_keep;
+    rocksdb_prefix + min_log_number_to_keep_str;
 const std::string DB::Properties::kTotalSstFilesSize =
     rocksdb_prefix + total_sst_files_size;
 const std::string DB::Properties::kLiveSstFilesSize =
     rocksdb_prefix + live_sst_files_size;
-const std::string DB::Properties::kBaseLevel = rocksdb_prefix + base_level;
+const std::string DB::Properties::kBaseLevel = rocksdb_prefix + base_level_str;
 const std::string DB::Properties::kEstimatePendingCompactionBytes =
     rocksdb_prefix + estimate_pending_comp_bytes;
 const std::string DB::Properties::kAggregatedTableProperties =

db/version_set.cc

@@ -2957,24 +2957,24 @@ Status VersionSet::LogAndApply(ColumnFamilyData* column_family_data,
       }
     } else {
       uint64_t max_log_number_in_batch  = 0;
-      uint64_t min_log_number_to_keep = 0;
+      uint64_t last_min_log_number_to_keep = 0;
       for (auto& e : batch_edits) {
         if (e->has_log_number_) {
           max_log_number_in_batch =
               std::max(max_log_number_in_batch, e->log_number_);
         }
         if (e->has_min_log_number_to_keep_) {
-          min_log_number_to_keep =
-              std::max(min_log_number_to_keep, e->min_log_number_to_keep_);
+          last_min_log_number_to_keep =
+              std::max(last_min_log_number_to_keep, e->min_log_number_to_keep_);
         }
       }
       if (max_log_number_in_batch != 0) {
         assert(column_family_data->GetLogNumber() <= max_log_number_in_batch);
         column_family_data->SetLogNumber(max_log_number_in_batch);
       }
-      if (min_log_number_to_keep != 0) {
+      if (last_min_log_number_to_keep != 0) {
         // Should only be set in 2PC mode.
-        MarkMinLogNumberToKeep2PC(min_log_number_to_keep);
+        MarkMinLogNumberToKeep2PC(last_min_log_number_to_keep);
       }
 
       AppendVersion(column_family_data, v);