Don't skip last level when calculating compaction stats

Summary: We have a bug where we don't report the last level's files as being compacted. This fixes it.

Test Plan: See the fix in action here: https://phabricator.fb.com/P19845738

Reviewers: MarkCallaghan, sdong

Reviewed By: sdong

Subscribers: yhchiang, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38727

db/internal_stats.cc

@@ -541,8 +541,7 @@ void InternalStats::DumpCFStats(std::string* value) {
   const VersionStorageInfo* vstorage = cfd_->current()->storage_info();
 
   int num_levels_to_check =
-      (cfd_->ioptions()->compaction_style != kCompactionStyleUniversal &&
-       cfd_->ioptions()->compaction_style != kCompactionStyleFIFO)
+      (cfd_->ioptions()->compaction_style != kCompactionStyleFIFO)
           ? vstorage->num_levels() - 1
           : 1;
 
@@ -555,7 +554,7 @@ void InternalStats::DumpCFStats(std::string* value) {
   }
   // Count # of files being compacted for each level
   std::vector<int> files_being_compacted(number_levels_, 0);
-  for (int level = 0; level < num_levels_to_check; ++level) {
+  for (int level = 0; level < number_levels_; ++level) {
     for (auto* f : vstorage->LevelFiles(level)) {
       if (f->being_compacted) {
         ++files_being_compacted[level];