Remove unnecessary error check in QuicStreamIdManager.

The method is only called when config is negotiated. By that time, it's impossible to have any incoming stream.

gfe-relnote: unused code. not protected.
PiperOrigin-RevId: 304059534
Change-Id: Ia0f7782f05e589b9bb1a0095d4437ad0974d3b2e

quic/core/quic_stream_id_manager.cc

diff --git a/quic/core/quic_stream_id_manager.cc b/quic/core/quic_stream_id_manager.cc
index 2878a9b..9a52ff3 100644
--- a/quic/core/quic_stream_id_manager.cc
+++ b/quic/core/quic_stream_id_manager.cc
@@ -89,11 +89,8 @@
 
 void QuicStreamIdManager::SetMaxOpenIncomingStreams(
     QuicStreamCount max_open_streams) {
-  if (max_open_streams < incoming_stream_count_) {
-    delegate_->OnStreamIdManagerError(
-        QUIC_MAX_STREAMS_ERROR, "Stream limit less than existing stream count");
-    return;
-  }
+  QUIC_BUG_IF(incoming_stream_count_ > 0)
+      << "non-zero stream count when setting max incoming stream.";
   QUIC_LOG_IF(WARNING, incoming_initial_max_open_streams_ != max_open_streams)
       << quiche::QuicheStrCat(
              unidirectional_ ? "unidirectional " : "bidirectional: ",