code: function createInstanceInjector(cache, providerInjector) {
  	const injector = createInjector(cache, function(servicename) {
  		let provider = providerInjector.get(servicename + PROVIDER_SUFFIX);
  		return injector.invoke(provider.$get, provider);
  	});
  
  	cache.$injector = injector;
  
  	return injector;
  }
docs: InstanceInjector holds provider-factory-instances or
  loads constructor from providerInjector and instantiates $get-factory
  @param  {Object} cache            instanceCache
  @param  {Object} providerInjector ProviderInjector-instance
  @return {Object}                  created injector instance