Fix a QUIC bug where the headers stream becomes flow control blocked and

net/quic/reliable_quic_stream.cc

Index: net/quic/reliable_quic_stream.cc
diff --git a/net/quic/reliable_quic_stream.cc b/net/quic/reliable_quic_stream.cc
index ff2123052f9c47c73337172c1b05bb5b406a73bb..a65203b600d268ff1df205b518f2e63623121517 100644
--- a/net/quic/reliable_quic_stream.cc
+++ b/net/quic/reliable_quic_stream.cc
@@ -532,6 +532,12 @@ void ReliableQuicStream::AddBytesConsumed(uint64 bytes) {
   }
 }
 
+void ReliableQuicStream::UpdateSendWindowOffset(uint64 new_window) {
+  if (flow_controller_.UpdateSendWindowOffset(new_window)) {
+    OnCanWrite();
+  }
+}
+
 bool ReliableQuicStream::IsFlowControlBlocked() {
   if (flow_controller_.IsBlocked()) {
     return true;