[Leveldb] Use std::{string,vector} instead of mojo::{String,Array}.

components/leveldb/public/cpp/util.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_LEVELDB_PUBLIC_CPP_UTIL_H_
 #define COMPONENTS_LEVELDB_PUBLIC_CPP_UTIL_H_
 
 #include "components/leveldb/public/interfaces/leveldb.mojom.h"
 
 namespace leveldb {
 
 class Slice;
 class Status;
 
 // Builds a mojo mojom::DatabaseError from a leveldb::Status object.
 mojom::DatabaseError LeveldbStatusToError(const leveldb::Status& s);
 
 // Creates a leveldb Status object form a database error and two optional
 // messages. A mojoification of the various static leveldb::Status
 // constructors.
 leveldb::Status DatabaseErrorToStatus(mojom::DatabaseError e,
                                       const Slice& msg,
                                       const Slice& msg2);
 
 // Builds a Slice pointing to the data inside |a|. This is not a type-converter
 // as it is not a copy operation; the returned Slice points into |a| and must
 // outlive |a|.
-leveldb::Slice GetSliceFor(const mojo::Array<uint8_t>& a);
+leveldb::Slice GetSliceFor(const std::vector<uint8_t>& a);
 
-// Copies the data that |s| points to into a mojo::Array.
-mojo::Array<uint8_t> GetArrayFor(const leveldb::Slice& s);
+// Copies the data that |s| points to into a std::vector.
+std::vector<uint8_t> GetVectorFor(const leveldb::Slice& s);
+
+std::string Uint8VectorToStdString(const std::vector<uint8_t>& input);
+
+std::vector<uint8_t> StdStringToUint8Vector(const std::string& input);
 
 }  // namespace leveldb
 
 #endif  // COMPONENTS_LEVELDB_PUBLIC_CPP_UTIL_H_