Replace a DCHECK with a return false, when processing invalid stop waiting data.

net/quic/core/quic_framer.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/core/quic_framer.h"
 
 #include <cstdint>
 #include <memory>
 
 #include "base/compiler_specific.h"
@@ skipping 1298 matching lines @@
 
 bool QuicFramer::ProcessStopWaitingFrame(QuicDataReader* reader,
                                          const QuicPacketHeader& header,
                                          QuicStopWaitingFrame* stop_waiting) {
   QuicPacketNumber least_unacked_delta = 0;
   if (!reader->ReadBytesToUInt64(header.public_header.packet_number_length,
                                  &least_unacked_delta)) {
     set_detailed_error("Unable to read least unacked delta.");
     return false;
   }
-  DCHECK_GE(header.packet_number, least_unacked_delta);
+  if (header.packet_number < least_unacked_delta) {
+    set_detailed_error("Invalid unacked delta.");
+    return false;
+  }
   stop_waiting->least_unacked = header.packet_number - least_unacked_delta;
 
   return true;
 }
 
 bool QuicFramer::ProcessRstStreamFrame(QuicDataReader* reader,
                                        QuicRstStreamFrame* frame) {
   if (!reader->ReadUInt32(&frame->stream_id)) {
     set_detailed_error("Unable to read stream_id.");
     return false;
@@ skipping 820 matching lines @@
   set_error(error);
   visitor_->OnError(this);
   return false;
 }
 
 Endianness QuicFramer::endianness() const {
   return quic_version_ > QUIC_VERSION_38 ? NETWORK_BYTE_ORDER : HOST_BYTE_ORDER;
 }
 
 }  // namespace net