8020789: Disable exporting of gc.heap_dump diagnostic command

Reviewed-by: fparain, ahgross

src/share/vm/services/diagnosticCommand.cpp

@@ -48,7 +48,7 @@ void DCmdRegistrant::register_dcmds(){
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<SystemGCDCmd>(full_export, true, false));
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<RunFinalizationDCmd>(full_export, true, false));
 #if INCLUDE_SERVICES // Heap dumping/inspection supported
-  DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<HeapDumpDCmd>(full_export, true, false));
+  DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<HeapDumpDCmd>(DCmd_Source_Internal | DCmd_Source_AttachAPI, true, false));
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ClassHistogramDCmd>(full_export, true, false));
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ClassStatsDCmd>(full_export, true, false));
 #endif // INCLUDE_SERVICES