Properly exit workers, plus small fixes.

src/lime/_internal/backend/html5/HTML5Thread.hx

@@ -55,8 +55,8 @@ class HTML5Thread {
 
 				try
 				{
-					job.dispatch();
 					Lib.global.onmessage = __current.dispatchMessage;
+					job.dispatch();
 				}
 				catch (e:Dynamic)
 				{
@@ -317,7 +317,6 @@ abstract WorkFunction<T:haxe.Constraints.Function>(WorkFunctionData<T>) from Wor
 			{
 				if (Context.defined("lime-warn-portability"))
 				{
-					trace(qualifiedFunc);
 					Context.warning("Value doesn't appear to be a static function.", func.pos);
 				}
 				return defaultOutput;
@@ -602,6 +601,6 @@ class Lib
 // specification only uses the former.
 @:forward
 abstract Transferable(Dynamic) #if macro from Dynamic
-	#else from js.lib.ArrayBuffer from js.html.MessagePort from js.html.ImageBitmap #end
+	#else from lime.utils.ArrayBuffer from js.html.MessagePort from js.html.ImageBitmap #end
 {
 }

src/lime/system/BackgroundWorker.hx

@@ -36,6 +36,8 @@ abstract BackgroundWorker(ThreadPool)
 	@:deprecated("Instead pass the callback to BackgroundWorker.run().")
 	@:noCompletion @:dox(hide) public var doWork(get, never):{ add: (Dynamic->Void) -> Void };
 
+	public var eventSource(get, never):Dynamic;
+
 	/**
 		__Call this only from the main thread.__
 
@@ -127,6 +129,11 @@ abstract BackgroundWorker(ThreadPool)
 
 	// Getters & Setters
 
+	private inline function get_eventSource():Dynamic
+	{
+		return this.eventSource != null ? this.eventSource.state : null;
+	}
+
 	private function get_doWork()
 	{
 		return {

src/lime/system/ThreadPool.hx

@@ -330,6 +330,9 @@ class ThreadPool extends WorkOutput
 
 				if (job.event == EXIT)
 				{
+					#if html5
+					Thread.current().destroy();
+					#end
 					return;
 				}