Fix HttpStreamParser fuzzer.

net/http/http_stream_parser_fuzzer.cc

 // Copyright 2016 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/http/http_stream_parser.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 111 matching lines @@
 
   net::HttpResponseInfo response_info;
   int result =
       parser.SendRequest("GET / HTTP/1.1\r\n", net::HttpRequestHeaders(),
                          &response_info, callback.callback());
   CHECK_EQ(net::OK, callback.GetResult(result));
 
   result = parser.ReadResponseHeaders(callback.callback());
   result = callback.GetResult(result);
 
-  if (result != net::OK)
+  if (result < 0)
     return 0;
 
   while (true) {
     // 64 exactly matches the maximum amount of data returned by a single
     // MockRead, as created above.
     scoped_refptr<net::IOBufferWithSize> io_buffer(
         new net::IOBufferWithSize(64));
     result = parser.ReadResponseBody(io_buffer.get(), io_buffer->size(),
                                      callback.callback());
 
     // Releasing the pointer to IOBuffer immediately is more likely to lead to a
     // use-after-free.
     io_buffer = nullptr;
 
     if (callback.GetResult(result) <= 0)
       break;
   }
 
   return 0;
 }