Update from https://crrev.com/316786

net/http/http_cache_transaction.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/http/http_cache_transaction.h"
 
 #include "build/build_config.h"
 
 #if defined(OS_POSIX)
 #include <unistd.h>
@@ skipping 2867 matching lines @@
   else if (mode_ & READ && entry_)
     cache_->DoneReadingFromEntry(entry_, this);
 
   partial_.reset(NULL);
   entry_ = NULL;
   mode_ = NONE;
 }
 
 void HttpCache::Transaction::FixHeadersForHead() {
   if (response_.headers->response_code() == 206) {
-    response_.headers->RemoveHeader("Content-Length");
     response_.headers->RemoveHeader("Content-Range");
     response_.headers->ReplaceStatusLine("HTTP/1.1 200 OK");
   }
 }
 
 void HttpCache::Transaction::TriggerAsyncValidation() {
   DCHECK(!request_->upload_data_stream);
   BoundNetLog async_revalidation_net_log(
       BoundNetLog::Make(net_log_.net_log(), NetLog::SOURCE_ASYNC_REVALIDATION));
   net_log_.AddEvent(
@@ skipping 372 matching lines @@
 
 void HttpCache::Transaction::OnIOComplete(int result) {
   // TODO(vadimt): Remove ScopedTracker below once crbug.com/422516 is fixed.
   tracked_objects::ScopedTracker tracking_profile(
       FROM_HERE_WITH_EXPLICIT_FUNCTION("422516 Transaction::OnIOComplete"));
 
   DoLoop(result);
 }
 
 }  // namespace net