// HPAContainerMetrics is enabled
  optional string type = 1;

  // object refers to a metric describing a single kubernetes object
  // (for example, hits-per-second on an Ingress object).
  // +optional
  optional ObjectMetricSource object = 2;

  // pods refers to a metric describing each pod in the current scale target
  // (for example, transactions-processed-per-second).  The values will be

  // or mis-configured policy definitions or bindings.
  //
  // A policy is invalid if spec.paramKind refers to a non-existent Kind.
  // A binding is invalid if spec.paramRef.name refers to a non-existent resource.
  //
  // failurePolicy does not define how validations that evaluate to false are handled.
  //