Complication error when using gcc 4.7.1.

Summary:
There is a compilation error while using gcc 4.7.1.
util/ldb_cmd.cc:381:3: error: ‘leveldb::ReadOptions::ReadOptions’ names the constructor, not the type
util/ldb_cmd.cc:381:37: error: expected ‘;’ before ‘read_options’
util/ldb_cmd.cc:381:49: error: statement cannot resolve address of overloaded function

Test Plan: make clean check

Reviewers: sheki, emayanke, zshao

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D7659

util/ldb_cmd.cc

@@ -378,8 +378,8 @@ void DBQuerier::DoCommand() {
     return;
   }
 
-  leveldb::ReadOptions::ReadOptions read_options;
-  leveldb::WriteOptions::WriteOptions write_options;
+  leveldb::ReadOptions read_options;
+  leveldb::WriteOptions write_options;
 
   std::string line;
   std::string key;