code: @Override
      public EnableMetricsCollectionResult enableMetricsCollection(EnableMetricsCollectionRequest request) {
          request = beforeClientExecution(request);
          return executeEnableMetricsCollection(request);
      }
docs: <p>
  Enables group metrics for the specified Auto Scaling group. For more information, see <a
  href="https://docs.aws.amazon.com/autoscaling/ec2/userguide/as-instance-monitoring.html">Monitoring Your Auto
  Scaling Groups and Instances</a> in the <i>Amazon EC2 Auto Scaling User Guide</i>.
  </p>
  
  @param enableMetricsCollectionRequest
  @return Result of the EnableMetricsCollection operation returned by the service.
  @throws ResourceContentionException
  You already have a pending update to an Amazon EC2 Auto Scaling resource (for example, an Auto Scaling
  group, instance, or load balancer).
  @sample AmazonAutoScaling.EnableMetricsCollection
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/autoscaling-2011-01-01/EnableMetricsCollection"
  target="_top">AWS API Documentation</a>