[Net] Propagate priority changes from URLRequest to HttpTransaction

net/url_request/url_request_job.cc

Index: net/url_request/url_request_job.cc
diff --git a/net/url_request/url_request_job.cc b/net/url_request/url_request_job.cc
index 6bbaa2935d92a68ef35555aecefdc7afc59cabb5..3c470a4ae7f0a88939feab514d13d279ecd06732 100644
--- a/net/url_request/url_request_job.cc
+++ b/net/url_request/url_request_job.cc
@@ -45,6 +45,9 @@ void URLRequestJob::SetUpload(UploadDataStream* upload) {
 void URLRequestJob::SetExtraRequestHeaders(const HttpRequestHeaders& headers) {
 }
 
+void URLRequestJob::SetPriority(RequestPriority priority) {
+}
+
 void URLRequestJob::Kill() {
   weak_factory_.InvalidateWeakPtrs();
   // Make sure the request is notified that we are done.  We assume that the