Add const accessors to URLRequest and UploadData.

net/url_request/url_request.cc

Index: net/url_request/url_request.cc
diff --git a/net/url_request/url_request.cc b/net/url_request/url_request.cc
index eac80f4b8947d291115923a3cf1092cd2ec1408c..8ea6325d819e072b5ad455b4c68867c90b7fa131 100644
--- a/net/url_request/url_request.cc
+++ b/net/url_request/url_request.cc
@@ -238,7 +238,11 @@ void URLRequest::set_upload(UploadData* upload) {
 }
 
 // Get the upload data directly.
-UploadData* URLRequest::get_upload() {
+const UploadData* URLRequest::get_upload() const {
+  return upload_.get();
+}
+
+UploadData* URLRequest::get_upload_mutable() {
   return upload_.get();
 }