leveldb: Reuse manifest (AKA logs) during open.

third_party/leveldatabase/env_chromium.h

 // Copyright (c) 2013 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
 #ifndef THIRD_PARTY_LEVELDATABASE_ENV_CHROMIUM_H_
 #define THIRD_PARTY_LEVELDATABASE_ENV_CHROMIUM_H_
 
 #include <deque>
 #include <set>
 #include <string>
@@ skipping 29 matching lines @@
   kLockFile,
   kUnlockFile,
   kGetTestDirectory,
   kNewLogger,
   kSyncParent,
   kGetChildren,
   kNewAppendableFile,
   kNumEntries
 };
 
+// The default value for leveldb::Options::reuse_logs. Currently log reuse is an
+// experimental feature in leveldb. More info at:
+// https://github.com/google/leveldb/commit/251ebf5dc70129ad3
+const bool kDefaultLogReuseOptionValue = true;
+
 const char* MethodIDToString(MethodID method);
 
 leveldb::Status MakeIOError(leveldb::Slice filename,
                             const std::string& message,
                             MethodID method,
                             base::File::Error error);
 leveldb::Status MakeIOError(leveldb::Slice filename,
                             const std::string& message,
                             MethodID method);
 
@@ skipping 132 matching lines @@
     void (*function)(void*);
   };
   typedef std::deque<BGItem> BGQueue;
   BGQueue queue_;
   LockTable locks_;
 };
 
 }  // namespace leveldb_env
 
 #endif  // THIRD_PARTY_LEVELDATABASE_ENV_CHROMIUM_H_