Let QUIC_VERSION_38 support IETF PADDING frame (1 byte frame with type 0x00) and respect NSTP conne…

net/quic/core/quic_data_writer.cc

Index: net/quic/core/quic_data_writer.cc
diff --git a/net/quic/core/quic_data_writer.cc b/net/quic/core/quic_data_writer.cc
index 3ac6450ba00339ad936d2c4215cde28d5c4fea1c..c4d4dfde0207e836bbb5d93ba89a0b2b745f665c 100644
--- a/net/quic/core/quic_data_writer.cc
+++ b/net/quic/core/quic_data_writer.cc
@@ -149,6 +149,10 @@ void QuicDataWriter::WritePadding() {
   length_ = capacity_;
 }
 
+bool QuicDataWriter::WritePaddingBytes(size_t count) {
+  return WriteRepeatedByte(0x00, count);
+}
+
 bool QuicDataWriter::WriteConnectionId(uint64_t connection_id) {
   if (FLAGS_quic_restart_flag_quic_big_endian_connection_id) {
     connection_id = QuicEndian::HostToNet64(connection_id);