Fix range deletion covering key in same SST file

Summary:
AddTombstones() needs to be before t->Get(), oops :'(
Closes https://github.com/facebook/rocksdb/pull/1576

Differential Revision: D4241041

Pulled By: ajkr

fbshipit-source-id: 781ceea

db/table_cache.cc

@@ -313,18 +313,7 @@ Status TableCache::Get(const ReadOptions& options,
         t = GetTableReaderFromHandle(handle);
       }
     }
-    if (s.ok()) {
-      get_context->SetReplayLog(row_cache_entry);  // nullptr if no cache.
-      s = t->Get(options, k, get_context, skip_filters);
-      get_context->SetReplayLog(nullptr);
-    } else if (options.read_tier == kBlockCacheTier && s.IsIncomplete()) {
-      // Couldn't find Table in cache but treat as kFound if no_io set
-      get_context->MarkKeyMayExist();
-      s = Status::OK();
-      done = true;
-    }
-  }
-  if (!done && s.ok() && get_context->range_del_agg() != nullptr &&
+    if (s.ok() && get_context->range_del_agg() != nullptr &&
         !options.ignore_range_deletions) {
       std::unique_ptr<InternalIterator> range_del_iter(
           t->NewRangeTombstoneIterator(options));
@@ -336,6 +325,17 @@ Status TableCache::Get(const ReadOptions& options,
             std::move(range_del_iter));
       }
     }
+    if (s.ok()) {
+      get_context->SetReplayLog(row_cache_entry);  // nullptr if no cache.
+      s = t->Get(options, k, get_context, skip_filters);
+      get_context->SetReplayLog(nullptr);
+    } else if (options.read_tier == kBlockCacheTier && s.IsIncomplete()) {
+      // Couldn't find Table in cache but treat as kFound if no_io set
+      get_context->MarkKeyMayExist();
+      s = Status::OK();
+      done = true;
+    }
+  }
 
 #ifndef ROCKSDB_LITE
   // Put the replay log in row cache only if something was found.