Remove duplicated dependency validation in nghttp2_session_reprioritize_stream

lib/nghttp2_session.c

@@ -601,15 +601,12 @@ nghttp2_session_reprioritize_stream(nghttp2_session *session,
   nghttp2_priority_spec pri_spec_default;
   const nghttp2_priority_spec *pri_spec = pri_spec_in;
 
+  assert(pri_spec->stream_id != stream->stream_id);
+
   if (!nghttp2_stream_in_dep_tree(stream)) {
     return 0;
   }
 
-  if (pri_spec->stream_id == stream->stream_id) {
-    return nghttp2_session_terminate_session_with_reason(
-        session, NGHTTP2_PROTOCOL_ERROR, "depend on itself");
-  }
-
   if (pri_spec->stream_id != 0) {
     dep_stream = nghttp2_session_get_stream_raw(session, pri_spec->stream_id);
 

lib/nghttp2_session.h

@@ -731,7 +731,8 @@ int nghttp2_session_update_local_settings(nghttp2_session *session,
 
 /*
  * Re-prioritize |stream|. The new priority specification is
- * |pri_spec|.
+ * |pri_spec|.  Caller must ensure that stream->hd.stream_id !=
+ * pri_spec->stream_id.
  *
  * This function returns 0 if it succeeds, or one of the following
  * negative error codes: