Add a constraint on how many requests can be outstanding for any given render (browser-side).

net/url_request/url_request.h

Index: net/url_request/url_request.h
===================================================================
--- net/url_request/url_request.h	(revision 9239)
+++ net/url_request/url_request.h	(working copy)
@@ -252,6 +252,9 @@
   // Set the upload data directly.
   void set_upload(net::UploadData* upload) { upload_ = upload; }
 
+  // Get the upload data directly.
+  net::UploadData* get_upload() { return upload_.get(); }
+
   // Returns true if the request has a non-empty message body to upload.
   bool has_upload() const { return upload_ != NULL; }
 
@@ -268,6 +271,8 @@
   // call it later.
   void SetExtraRequestHeaders(const std::string& headers);
 
+  const std::string& extra_request_headers() { return extra_request_headers_; }
+
   // Returns the current load state for the request.
   net::LoadState GetLoadState() const;