mojo leveldb: Add an iteration interface.

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_UTIL_H_
-#define COMPONENTS_LEVELDB_UTIL_H_
+#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;
 
 DatabaseError LeveldbStatusToError(const leveldb::Status& s);
 
+leveldb::Status DatabaseErrorToStatus(DatabaseError e,

[jam, 2016/04/07 16:06:01]

nit: please add a comment for all these public methods

+                                      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);
 
+mojo::Array<uint8_t> GetArrayFor(const leveldb::Slice& s);
+
 }  // namespace leveldb
 
-#endif  // COMPONENTS_LEVELDB_UTIL_H_
+#endif  // COMPONENTS_LEVELDB_PUBLIC_CPP_UTIL_H_