Increase the QUIC header size limit to 256KB from 16KB.

net/quic/chromium/mock_quic_data.cc

Index: net/quic/chromium/mock_quic_data.cc
diff --git a/net/quic/chromium/mock_quic_data.cc b/net/quic/chromium/mock_quic_data.cc
index f36029b2a4fb0aa6749d65e63a01d04e966724d4..63e2db04cd794b16a1bb551b140c3bf2eb729366 100644
--- a/net/quic/chromium/mock_quic_data.cc
+++ b/net/quic/chromium/mock_quic_data.cc
@@ -38,6 +38,12 @@ void MockQuicData::AddWrite(std::unique_ptr<QuicEncryptedPacket> packet) {
   packets_.push_back(std::move(packet));
 }
 
+void MockQuicData::AddAsyncWrite(std::unique_ptr<QuicEncryptedPacket> packet) {
+  writes_.push_back(
+      MockWrite(ASYNC, packet->data(), packet->length(), sequence_number_++));
+  packets_.push_back(std::move(packet));
+}
+
 void MockQuicData::AddWrite(IoMode mode, int rv) {
   writes_.push_back(MockWrite(mode, rv, sequence_number_++));
 }