Removing unused variables to fix build

Summary: Removing two unused variables that prevented compilation.

Test Plan: make all

Reviewers: rven, sdong, yhchiang, anthony, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D44991

db/forward_iterator.cc

@@ -646,7 +646,6 @@ void ForwardIterator::DeleteCurrentIter() {
   }
 
   for (int32_t level = 1; level < vstorage->num_levels(); ++level) {
-    const std::vector<FileMetaData*>& level_files = vstorage->LevelFiles(level);
     if (level_iters_[level - 1] == nullptr) {
       continue;
     }

db/forward_iterator.h

@@ -104,7 +104,6 @@ class ForwardIterator : public Iterator {
   Status immutable_status_;
   bool valid_;
   bool has_iter_trimmed_for_upper_bound_;
-  bool has_iter_filtered_by_range_;
   Slice smallest_file_key_bound;
 
   IterKey prev_key_;