8254889: name_and_sig_as_C_string usages in frame coding without ResourceMark

Reviewed-by: dholmes

src/hotspot/share/runtime/frame.cpp

@@ -1141,6 +1141,8 @@ void frame::interpreter_frame_verify_monitor(BasicObjectLock* value) const {
 #endif
 
 #ifndef PRODUCT
+// callers need a ResourceMark because of name_and_sig_as_C_string() usage,
+// RA allocated string is returned to the caller
 void frame::describe(FrameValues& values, int frame_no) {
   // boundaries: sp and the 'real' frame pointer
   values.describe(-1, sp(), err_msg("sp for #%d", frame_no), 1);