Fetch, XHR: Use ", " as header list value separator.

third_party/WebKit/Source/platform/loader/fetch/ResourceRequest.cpp

 /*
  * Copyright (C) 2003, 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2009, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 310 matching lines @@
 void ResourceRequest::SetPriority(ResourceLoadPriority priority,
                                   int intra_priority_value) {
   priority_ = priority;
   intra_priority_value_ = intra_priority_value;
 }
 
 void ResourceRequest::AddHTTPHeaderField(const AtomicString& name,
                                          const AtomicString& value) {
   HTTPHeaderMap::AddResult result = http_header_fields_.Add(name, value);
   if (!result.is_new_entry)
-    result.stored_value->value = result.stored_value->value + ',' + value;
+    result.stored_value->value = result.stored_value->value + ", " + value;
 }
 
 void ResourceRequest::AddHTTPHeaderFields(const HTTPHeaderMap& header_fields) {
   HTTPHeaderMap::const_iterator end = header_fields.end();
   for (HTTPHeaderMap::const_iterator it = header_fields.begin(); it != end;
        ++it)
     AddHTTPHeaderField(it->key, it->value);
 }
 
 void ResourceRequest::ClearHTTPHeaderField(const AtomicString& name) {
@@ skipping 76 matching lines @@
   // layer.
   if (HttpMethod() == HTTPNames::GET || HttpMethod() == HTTPNames::HEAD)
     return false;
 
   // For non-GET and non-HEAD methods, always send an Origin header so the
   // server knows we support this feature.
   return true;
 }
 
 }  // namespace blink