workers: basic event loop (#3828)

* establish basic event loop for workers
* make "self.close()" inside worker
* remove "runWorkerMessageLoop() - instead manually call global function 
  in Rust when message arrives. This is done in preparation for structured clone
* refactor "WorkerChannel" and use distinct structs for internal 
  and external channels;  "WorkerChannelsInternal" and "WorkerHandle"
* move "State.worker_channels_internal" to "Worker.internal_channels"
* add "WorkerEvent" enum for child->host communication; 
  currently "Message(Buf)" and  "Error(ErrBox)" variants are supported
* add tests for nested workers
* add tests for worker throwing error on startup

1 files changed, 2 insertions, 2 deletions

diff --git a/cli/js/dispatch.ts b/cli/js/dispatch.ts
index 1a6b6528d..4493d3771 100644
--- a/cli/js/dispatch.ts
+++ b/cli/js/dispatch.ts
@@ -43,10 +43,10 @@ export let OP_REVOKE_PERMISSION: number;
 export let OP_REQUEST_PERMISSION: number;
 export let OP_CREATE_WORKER: number;
 export let OP_HOST_POST_MESSAGE: number;
-export let OP_HOST_CLOSE_WORKER: number;
+export let OP_HOST_TERMINATE_WORKER: number;
 export let OP_HOST_GET_MESSAGE: number;
 export let OP_WORKER_POST_MESSAGE: number;
-export let OP_WORKER_GET_MESSAGE: number;
+export let OP_WORKER_CLOSE: number;
 export let OP_RUN: number;
 export let OP_RUN_STATUS: number;
 export let OP_KILL: number;