Allow no content-type for POST, PUT and PATCH methods.

net/url_request/url_fetcher_core.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_fetcher_core.h"
 
 #include "base/bind.h"
 #include "base/files/file_util_proxy.h"
 #include "base/logging.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 716 matching lines @@
                           url_request_create_data_callback_.Run());
   }
 
   switch (request_type_) {
     case URLFetcher::GET:
       break;
 
     case URLFetcher::POST:
     case URLFetcher::PUT:
     case URLFetcher::PATCH:
-      DCHECK(!upload_content_type_.empty());
+      // |upload_content_type_| must be set if there is (non-empty) upload
+      // content.
+      DCHECK(!(is_chunked_upload_ || upload_content_) ||
+             !upload_content_type_.empty());

[mmenke, 2013/02/06 16:23:58]

Rather than this, I'd prefer a design that requires an explicit call to
SetUploadData("", "").

The simplest way to do this may be to move this DCHECK into the two SetUpload
routines, allowing content type to be empty in SetUploadData if the content is
empty, but never in SetChunkedUpload.

Then you DCHECK(is_chunked_upload_ || upload_content_) here.  Sound reasonable?

You could dig into upload_content_ here to figure out if it's 0-length, but
think that's needlessly complicated.

[hidehiko, 2013/02/06 17:19:49]

Indeed. I just allowed SetUploadData("", "") for empty content type to be
conservative. This is because UploadDataStream given via SetUploadDataStream may
not be initialized yet, so it may be impossible to take the total size, that is,
we cannot check emptiness of the upload content there.

What do you think?

 
       request_->set_method(
           request_type_ == URLFetcher::POST ? "POST" :
           request_type_ == URLFetcher::PUT ? "PUT" : "PATCH");
-      extra_request_headers_.SetHeader(HttpRequestHeaders::kContentType,
-                                       upload_content_type_);
+      if (!upload_content_type_.empty())
+        extra_request_headers_.SetHeader(HttpRequestHeaders::kContentType,
+                                         upload_content_type_);

[mmenke, 2013/02/06 16:23:58]

nit:  Use braces when body is more than one line.

[hidehiko, 2013/02/06 17:19:49]

Done.

       if (upload_content_)
         request_->set_upload(upload_content_.Pass());
       current_upload_bytes_ = -1;
       // TODO(kinaba): http://crbug.com/118103. Implement upload callback in the
       //  layer and avoid using timer here.
       upload_progress_checker_timer_.reset(
           new base::RepeatingTimer<URLFetcherCore>());
       upload_progress_checker_timer_->Start(
           FROM_HERE,
           base::TimeDelta::FromMilliseconds(kUploadProgressTimerInterval),
@@ skipping 310 matching lines @@
 }
 
 void URLFetcherCore::InformDelegateDownloadDataInDelegateThread(
     scoped_ptr<std::string> download_data) {
   DCHECK(delegate_task_runner_->BelongsToCurrentThread());
   if (delegate_)
     delegate_->OnURLFetchDownloadData(fetcher_, download_data.Pass());
 }
 
 }  // namespace net