Create EnvOptions using sanitized DB Options

Summary: Now EnvOptions uses unsanitized DB options. bytes_per_sync is tuned off when rate_limiter is used, but this change doesn't take effort.

Test Plan: See different I/O pattern in db_bench running fillseq.

Reviewers: yhchiang, kradhakrishnan, rven, anthony, igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D36723

db/db_impl.cc

@@ -232,7 +232,7 @@ DBImpl::DBImpl(const DBOptions& options, const std::string& dbname)
       last_stats_dump_time_microsec_(0),
       next_job_id_(1),
       flush_on_destroy_(false),
-      env_options_(options),
+      env_options_(db_options_),
 #ifndef ROCKSDB_LITE
       wal_manager_(db_options_, env_options_),
 #endif  // ROCKSDB_LITE