Changelog

• Add server interceptors support (#2650) (details in gRFC L112)
• Deprecate Server#start (#2597) (details in gRFC L107)
• Add Server#unbind (#2612) (details in gRFC L109)
• Add Server#drain (#2616) (details in gRFC L111)
• Export type VerifyOptions (#2637 contributed by @chakhsu)

Experimental API Changes

• Added:
  • Endpoint
  • endpointToString
  • endpointHasAddress
  • LeafLoadBalancer
  • HealthListener
  • SubchannelInterface#isHealthy
  • SubchannelInterface#addHealthStateWatcher
  • SubchannelInterface#removeHealthStateWatcher
  • SubchannelWrapper#setHealthy
  • selectLbConfigFromList
  • parseLoadBalancingConfig
  • OutlierDetectionRawConfig
  • EndpointMap
• Moved out of the experimental namespace:
  • ServiceConfig
  • MethodConfig
  • LoadBalancingConfig (now a simple raw object type)
  • RetryPolicy
• Removed:
  • getFirstUsableConfig
  • validateLoadBalancingConfig
  • OutlierDetectionLoadBalancingConfig
• Modified:
  • LoadBalancer#updateAddressList: The first argument now has type Endpoint[] instead of SubchannelAddress[]
  • ResolverListener#onSuccessfulResolution: The first argument now has type Endpoint[] instead of SubchannelAddress[]
  • registerLoadBalancerType: The second argument, a LoadBalancerConstructor now takes a second argument options: ChannelOptions
  • ConfigSelector: Now accepts an additional argument channelId: number
  • QueuePicker: The constructor now accepts an additional optional argument childPicker: Picker, which the QueuePicker instance will delegate to if provided.