grpc/grpc-node @grpc/grpc-js@1.4.0 on GitHub

Add Channelz support (specification here) (#1915)
This adds the following public APIs:
- getChannelzServiceDefinition(): ServiceDefinition
- getChannelzHandlers(): ServiceHandler
  These two can be used together to serve the channelz service as follows:
```
server.addService(getChannelzServiceDefinition(), getChannelzHandlers());
```
- Channel#getChannelzRef(): ChannelRef
- Server#getChannelzRef(): ServerRef
Add the admin interface (specification here) (#1915)
Currently the only admin service is Channelz, but more can be added in the future. This adds the following public api:
- addAdminServicesToServer(server: Server): void
Add support for timeouts in service configs (#1785)
Remove type restrictions on Channel options (#1916)
Report ECONNRESET errors with the UNAVAILABLE status code (#1878)
Tighten type checking for credentials argument to Server#bindAsync (#1852)
Pass log messages to different log functions based on severity in custom loggers, and note the severity in the default logger output (#1851)
Add logging for TLS errors when connecting through a proxy (#1842)
Refactor code to eliminate runtime dependency cycles (#1829)

Changes to experimental APIs

Added exports of the following:
- Duration
- registerAdminService
- createChildChannelControlHelper
Picker#extraFilterFactory has been replaced with Picker#extraFilterFactories with type FilterFactory<Filter>[]
CallConfig has a new property dynamicFilterFactories with type FilterFactory<Filter>[]
ChannelControlHelper has the new properties addChannelzChild(child: ChannelRef | SubchannelRef) and removeChannelzChild(child: ChannelRef | SubchannelRef)