Factor out common Element struct from BlobData and ResourceRequestBody

content/public/common/common_param_traits.h

Index: content/public/common/common_param_traits.h
diff --git a/content/public/common/common_param_traits.h b/content/public/common/common_param_traits.h
index 0742c79481711fe9494595e30867dda0d1f48b69..1d2531f6a44e7b5998cdb081f384b9a07b57470a 100644
--- a/content/public/common/common_param_traits.h
+++ b/content/public/common/common_param_traits.h
@@ -23,6 +23,7 @@
 #include "net/url_request/url_request_status.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/surface/transport_dib.h"
+#include "webkit/base/data_element.h"
 
 class SkBitmap;
 
@@ -86,6 +87,14 @@ struct CONTENT_EXPORT ParamTraits<scoped_refptr<
   static void Log(const param_type& p, std::string* l);
 };
 
+template <>
+struct CONTENT_EXPORT ParamTraits<webkit_base::DataElement> {
+  typedef webkit_base::DataElement param_type;
+  static void Write(Message* m, const param_type& p);
+  static bool Read(const Message* m, PickleIterator* iter, param_type* r);
+  static void Log(const param_type& p, std::string* l);
+};
+
 template<>
 struct CONTENT_EXPORT ParamTraits<net::HostPortPair> {
   typedef net::HostPortPair param_type;