Configring node js.

node_modules/core-js/library/modules/es7.reflect.delete-metadata.js

@@ -0,0 +1,15 @@
+var metadata               = require('./_metadata')
+  , anObject               = require('./_an-object')
+  , toMetaKey              = metadata.key
+  , getOrCreateMetadataMap = metadata.map
+  , store                  = metadata.store;
+
+metadata.exp({deleteMetadata: function deleteMetadata(metadataKey, target /*, targetKey */){
+  var targetKey   = arguments.length < 3 ? undefined : toMetaKey(arguments[2])
+    , metadataMap = getOrCreateMetadataMap(anObject(target), targetKey, false);
+  if(metadataMap === undefined || !metadataMap['delete'](metadataKey))return false;
+  if(metadataMap.size)return true;
+  var targetMetadata = store.get(target);
+  targetMetadata['delete'](targetKey);
+  return !!targetMetadata.size || store['delete'](target);
+}});