A mixin for acquiring object properties without modifying the prototype chain.

Mixin.js

function mixin(receiver, supplier) {
 if(Object.getOwnPropertyDescriptor) {
   Object.keys(supplier).forEach(function(prop) {
     let descriptor = Object.getOwnPropertyDescriptor(supplier, prop);
     Object.defineProperty(receiver, prop, descriptor);
   });
 } else {  // For older browsers, does not support accessor properties
  for(let prop in supplier) {
   if (supplier.hasOwnProperty(prop) {
    receiver[prop] = supplier[prop];    
   }
  }
 }
 return receiver;
}