Reland https://codereview.chromium.org/1271593002/ which was reverted

net/url_request/url_request_simple_job.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/url_request/url_request_simple_job.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
@@ skipping 30 matching lines @@
 }
 
 void URLRequestSimpleJob::Start() {
   // Start reading asynchronously so that all error reporting and data
   // callbacks happen as they would for network requests.
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
       base::Bind(&URLRequestSimpleJob::StartAsync, weak_factory_.GetWeakPtr()));
 }
 
+void URLRequestSimpleJob::Kill() {
+  weak_factory_.InvalidateWeakPtrs();
+  URLRangeRequestJob::Kill();
+}
+
 bool URLRequestSimpleJob::GetMimeType(std::string* mime_type) const {
   *mime_type = mime_type_;
   return true;
 }
 
 bool URLRequestSimpleJob::GetCharset(std::string* charset) {
   *charset = charset_;
   return true;
 }
 
@@ skipping 84 matching lines @@
     next_data_offset_ = byte_range_.first_byte_position();
     set_expected_content_size(byte_range_.last_byte_position() -
                               next_data_offset_ + 1);
     NotifyHeadersComplete();
   } else {
     NotifyStartError(URLRequestStatus(URLRequestStatus::FAILED, result));
   }
 }
 
 }  // namespace net