Don't set QUIC's write alarm if we are connection flow control blocked.

net/quic/test_tools/quic_session_peer.cc

Index: net/quic/test_tools/quic_session_peer.cc
diff --git a/net/quic/test_tools/quic_session_peer.cc b/net/quic/test_tools/quic_session_peer.cc
index 080643b206998e61418d0ffd2753662e3c32f986..a46b6fe7e4e7451c1204e0cbd5561e7e23bfc244 100644
--- a/net/quic/test_tools/quic_session_peer.cc
+++ b/net/quic/test_tools/quic_session_peer.cc
@@ -27,6 +27,12 @@ QuicHeadersStream* QuicSessionPeer::GetHeadersStream(QuicSession* session) {
 }
 
 // static
+void QuicSessionPeer::SetHeadersStream(QuicSession* session,
+                                       QuicHeadersStream* headers_stream) {
+  session->headers_stream_.reset(headers_stream);
+}
+
+// static
 QuicWriteBlockedList* QuicSessionPeer::GetWriteblockedStreams(
     QuicSession* session) {
   return &session->write_blocked_streams_;