Replace QuicAckListenerInterface* with scoped_refptr<QuicAckListenerInterface>.

net/quic/core/quic_spdy_stream.cc

Index: net/quic/core/quic_spdy_stream.cc
diff --git a/net/quic/core/quic_spdy_stream.cc b/net/quic/core/quic_spdy_stream.cc
index 6c9335b76e87d82693766893cee84f3e312401ce..8db10432601ae60e8e4d9ae3c5b5f0c637c6b87d 100644
--- a/net/quic/core/quic_spdy_stream.cc
+++ b/net/quic/core/quic_spdy_stream.cc
@@ -61,7 +61,7 @@ void QuicSpdyStream::StopReading() {
 size_t QuicSpdyStream::WriteHeaders(
     SpdyHeaderBlock header_block,
     bool fin,
-    QuicAckListenerInterface* ack_notifier_delegate) {
+    const scoped_refptr<QuicAckListenerInterface>& ack_notifier_delegate) {
   size_t bytes_written = spdy_session_->WriteHeaders(
       id(), std::move(header_block), fin, priority_, ack_notifier_delegate);
   if (fin) {
@@ -75,13 +75,13 @@ size_t QuicSpdyStream::WriteHeaders(
 void QuicSpdyStream::WriteOrBufferBody(
     const string& data,
     bool fin,
-    QuicAckListenerInterface* ack_notifier_delegate) {
+    const scoped_refptr<QuicAckListenerInterface>& ack_notifier_delegate) {
   WriteOrBufferData(data, fin, ack_notifier_delegate);
 }
 
 size_t QuicSpdyStream::WriteTrailers(
     SpdyHeaderBlock trailer_block,
-    QuicAckListenerInterface* ack_notifier_delegate) {
+    const scoped_refptr<QuicAckListenerInterface>& ack_notifier_delegate) {
   if (fin_sent()) {
     QUIC_BUG << "Trailers cannot be sent after a FIN.";
     return 0;
@@ -330,7 +330,7 @@ QuicConsumedData QuicSpdyStream::WritevDataInner(
     QuicIOVector iov,
     QuicStreamOffset offset,
     bool fin,
-    QuicAckListenerInterface* ack_notifier_delegate) {
+    const scoped_refptr<QuicAckListenerInterface>& ack_notifier_delegate) {
   if (spdy_session_->headers_stream() != nullptr &&
       spdy_session_->force_hol_blocking()) {
     return spdy_session_->headers_stream()->WritevStreamData(