Add check for that reader is not null in GetPostData

headless/public/util/generic_url_request_job.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 "headless/public/util/generic_url_request_job.h"
 
 #include <string.h>
 #include <algorithm>
 
 #include "base/logging.h"
@@ skipping 254 matching lines @@
   const net::UploadDataStream* stream = request_->get_upload();
   if (!stream->GetElementReaders())
     return "";
 
   if (stream->GetElementReaders()->size() == 0)
     return "";
 
   DCHECK_EQ(1u, stream->GetElementReaders()->size());
   const net::UploadBytesElementReader* reader =
       (*stream->GetElementReaders())[0]->AsBytesReader();
+  if (!reader)
+    return "";
   return std::string(reader->bytes(), reader->length());
 }
 
 const Request* GenericURLRequestJob::GetRequest() const {
   return this;
 }
 
 void GenericURLRequestJob::AllowRequest() {
   if (!origin_task_runner_->RunsTasksOnCurrentThread()) {
     origin_task_runner_->PostTask(
@@ skipping 49 matching lines @@
   }
 
   mock_response_ = std::move(mock_response);
 
   OnFetchCompleteExtractHeaders(request_->url(),
                                 mock_response_->response_data.data(),
                                 mock_response_->response_data.size());
 }
 
 }  // namespace headless