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

components/leveldb/public/cpp/util.h

Index: components/leveldb/public/cpp/util.h
diff --git a/components/leveldb/public/cpp/util.h b/components/leveldb/public/cpp/util.h
index 44f733af30d9806d3ec777beafef2acb7d6611ab..23e1e1d508fb3f362ac62844ab0b988d9483f20a 100644
--- a/components/leveldb/public/cpp/util.h
+++ b/components/leveldb/public/cpp/util.h
@@ -25,10 +25,14 @@ leveldb::Status DatabaseErrorToStatus(mojom::DatabaseError e,
 // 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